Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
Search: a328390 -id:a328390
     Sort: relevance | references | number | modified | created      Format: long | short | data
Maximal digit value used when n is written in primorial base (cf. A049345).
+10
54
0, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
OFFSET
0,5
FORMULA
a(n) = A051903(A276086(n)).
a(A276156(n)) = 1 for all n >= 1.
a(n) <= A276150(n) for all n >= 0.
From Antti Karttunen, Oct 29 2019: (Start)
a(n) = A061395(A328835(n)).
For n >= 1, a(n) < A000040(A235224(n)) and a(n) <= 1 + A328391(n).
For all n >= 1, a(n) = 1+A051903(A328572(n)).
a(A276086(n)) = A328389(n), a(A276087(n)) = A328394(n), a(A328403(n)) = A328398(n).
a(A327860(n)) = A328392(n), a(A003415(n)) = A328390(n), a(A328316(n)) = A328322(n).
(End)
EXAMPLE
For n = 2105, which could be expressed in primorial base for example as "T0021" (where T here stands for the digit value ten), or maybe more elegantly as [10,0,0,2,1] as 2105 = 10*A002110(4) + 2*A002110(1) + 1*A002110(0). The maximum value of these digits is 10, thus a(2105) = 10.
MATHEMATICA
With[{b = MixedRadix[Reverse@ Prime@ Range@ 20]}, Array[Max@ IntegerDigits[#, b] &, 105, 0]] (* Michael De Vlieger, Oct 30 2019 *)
PROG
(PARI) A328114(n) = { my(i=0, m=0, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m = max(m, (n%nextpr)/pr); n-=(n%nextpr)); pr=nextpr); (m); };
(PARI) A328114(n) = { my(s=0, p=2); while(n, s = max(s, (n%p)); n = n\p; p = nextprime(1+p)); (s); }; \\ (Faster, no unnecessary construction of primorials) - Antti Karttunen, Oct 29 2019
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 12 2019
STATUS
approved
Maximal digit value in primorial base expansion of A276086(n): a(n) = A328114(A276086(n)).
+10
13
1, 1, 1, 1, 1, 3, 2, 2, 2, 1, 2, 3, 4, 3, 2, 5, 2, 2, 4, 2, 5, 4, 5, 10, 6, 6, 8, 6, 5, 9, 1, 2, 3, 2, 2, 4, 2, 2, 3, 1, 3, 3, 5, 4, 3, 5, 7, 4, 4, 8, 3, 3, 4, 9, 9, 8, 7, 11, 4, 8, 3, 3, 4, 4, 3, 4, 2, 2, 3, 7, 10, 10, 5, 4, 6, 3, 8, 9, 7, 5, 10, 10, 10, 8, 5, 5, 8, 6, 9, 7, 4, 4, 6, 9, 4, 7, 8, 5, 3, 5, 7, 4, 7, 7, 11, 9
OFFSET
0,6
FORMULA
a(n) = A328114(A276086(n)).
a(n) = A051903(A276087(n)).
PROG
(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328114(n) = { my(s=0, p=2); while(n, s = max(s, (n%p)); n = n\p; p = nextprime(1+p)); (s); };
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 15 2019
STATUS
approved
Maximal exponent in the prime factorization of A327860(n): a(n) = A051903(A327860(n)).
+10
13
0, 0, 1, 1, 1, 0, 1, 3, 1, 1, 1, 1, 2, 1, 1, 4, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 0, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 3, 1, 1, 1, 1, 1, 2, 2, 7, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 4, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2
OFFSET
1,8
FORMULA
a(A002110(n)) = 0 for all n >= 0.
For all n >= 1, a(n) >= A328114(n)-1. [Because arithmetic derivative will decrease the maximal prime exponent (A051903) of its argument by at most one]
PROG
(PARI)
A051903(n) = if((1==n), 0, vecmax(factor(n)[, 2]));
A327860(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); (s*m); };
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 15 2019
STATUS
approved
Maximal digit value in primorial base expansion of A327860(n): a(n) = A328114(A327860(n)).
+10
8
0, 1, 1, 2, 1, 3, 1, 1, 1, 1, 1, 4, 2, 2, 4, 6, 1, 3, 2, 2, 4, 5, 6, 7, 3, 7, 10, 7, 6, 9, 1, 1, 2, 2, 3, 5, 2, 4, 2, 1, 3, 4, 3, 5, 2, 6, 9, 4, 3, 10, 3, 6, 8, 2, 8, 5, 7, 7, 5, 10, 2, 2, 3, 4, 2, 6, 4, 2, 6, 9, 3, 4, 4, 5, 6, 9, 6, 7, 5, 7, 9, 5, 11, 10, 4, 3, 5, 11, 16, 7, 4, 3, 5, 2, 5, 6, 5, 7, 4, 6, 8, 10, 5, 9, 12, 11
OFFSET
0,4
FORMULA
PROG
(PARI)
A327860(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); (s*m); };
A328114(n) = { my(s=0, p=2); while(n, s = max(s, (n%p)); n = n\p; p = nextprime(1+p)); (s); };
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 15 2019
STATUS
approved
Numbers k such that the primorial base representation of their arithmetic derivative does not contain digits larger than 1.
+10
6
0, 1, 2, 3, 5, 7, 9, 10, 11, 13, 14, 15, 16, 17, 19, 23, 28, 29, 30, 31, 37, 41, 43, 45, 47, 53, 58, 59, 61, 62, 67, 71, 73, 74, 79, 83, 87, 89, 97, 101, 103, 107, 108, 109, 112, 113, 127, 131, 136, 137, 139, 149, 151, 155, 157, 161, 163, 167, 173, 179, 181, 189, 191, 193, 197, 198, 199, 203, 209, 210, 211, 212, 217
OFFSET
1,3
COMMENTS
Numbers k for which A328390(k) <= 1, numbers k such that A003415(k) is in A276156.
Numbers k such that A327859(k) = A276086(A003415(k)) is squarefree.
FORMULA
For all n > 2, A328390(a(n)) = A328114(A003415(a(n))) = 1.
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
ismaxprimobasedigit_at_most(n, k) = { my(s=0, p=2); while(n, if((n%p)>k, return(0)); n = n\p; p = nextprime(1+p)); (1); };
isA341518(n) = ismaxprimobasedigit_at_most(A003415(n), 1); \\ Antti Karttunen, Feb 03 2024
CROSSREFS
Positions of nonzero terms in A341517.
Subsequences: A000040, A327978, A328232, A369647 (terms k where A051903(k) obtains novel values).
Cf. also A327969.
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 28 2021
STATUS
approved
a(n) = mu(A327859(n)), where mu is the Möbius function, A008683.
+10
5
1, 1, -1, -1, 0, -1, 0, -1, 0, -1, 1, -1, 0, -1, -1, 1, 1, -1, 0, -1, 0, 0, 0, -1, 0, 0, 0, 0, 1, -1, 1, -1, 0, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, -1, 0, 1, 0, -1, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, -1, 0, -1, -1, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, -1, 1, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, 0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, -1, 0, 0
OFFSET
0
FORMULA
For all n > 1, abs(a(n)) = [A328390(n)==1], where [ ] is the Iverson bracket.
a(p) = -1 for all primes p.
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A341517(n) = moebius(A327859(n));
CROSSREFS
Absolute values give the characteristic function sequence for A341518.
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 28 2021
STATUS
approved
Numbers k such that the maximal digit value in primorial base expansion of the arithmetic derivative of k is less than the maximal exponent in the prime factorization of k.
+10
5
8, 9, 16, 24, 28, 32, 40, 45, 48, 81, 96, 108, 112, 120, 125, 128, 136, 160, 184, 189, 192, 198, 208, 212, 225, 236, 244, 250, 256, 270, 288, 296, 352, 361, 459, 507, 625, 640, 768, 800, 832, 864, 896, 928, 960, 972, 1008, 1024, 1056, 1088, 1104, 1120, 1152, 1168, 1184, 1232, 1272, 1280, 1320, 1344, 1350, 1408, 1440
OFFSET
1,1
COMMENTS
Numbers k such that A328390(k) < A051903(k).
Numbers k for which A051903(A327859(n)) < A051903(k).
These seem to be rarer than A351075. All terms are nonsquarefree.
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A051903(n) = if((1==n), 0, vecmax(factor(n)[, 2]));
A328114(n) = { my(s=0, p=2); while(n, s = max(s, (n%p)); n = n\p; p = nextprime(1+p)); (s); };
isA351098(n) = (A328114(A003415(n)) < A051903(n));
(PARI) \\ Or see A369637.
CROSSREFS
Positions of negative terms in A351097. Subsequence of A013929 and of A351099.
Cf. A003415, A051903, A276086, A327859, A328390, A369637 (characteristic function).
Cf. also A351075.
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 03 2022
STATUS
approved
Difference between {the maximal digit value in primorial base expansion of the arithmetic derivative of n} and {the maximal exponent in the prime factorization of n}.
+10
4
0, 0, 0, 0, 0, 1, 0, -1, -1, 0, 0, 0, 0, 0, 0, -3, 0, 1, 0, 2, 1, 1, 0, -1, 0, 1, 1, -1, 0, 0, 0, -2, 1, 2, 1, 0, 0, 2, 1, -1, 0, 1, 0, 1, -1, 3, 0, -1, 0, 0, 2, 2, 0, 0, 1, 0, 2, 0, 0, 1, 0, 0, 1, 0, 2, 1, 0, 0, 3, 3, 0, 2, 0, 0, 2, 1, 2, 1, 0, 1, -1, 1, 0, 2, 2, 1, 0, 1, 0, 2, 2, 1, 1, 2, 3, -3, 0, 0, 0, 2, 0, 2, 0, 2, 1
OFFSET
1,16
LINKS
FORMULA
a(n) = A328390(n) - A051903(n) = A051903(A327859(n)) - A051903(n).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A051903(n) = if((1==n), 0, vecmax(factor(n)[, 2]));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A351097(n) = (A051903(A327859(n)) - A051903(n));
CROSSREFS
Cf. A003415, A051903, A276086, A327859, A328390, A351098 (positions of negative terms), A351099.
Cf. also A350074, A351074.
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 03 2022
STATUS
approved
Composite numbers k such that the maximal digit value in primorial base expansion of the arithmetic derivative of k is not larger than the maximal exponent in the prime factorization of k.
+10
2
4, 8, 9, 10, 12, 14, 15, 16, 24, 25, 28, 30, 32, 36, 40, 45, 48, 49, 50, 54, 56, 58, 62, 64, 68, 74, 81, 87, 96, 98, 99, 108, 112, 120, 125, 128, 136, 155, 156, 160, 161, 162, 184, 189, 192, 196, 198, 203, 204, 208, 209, 210, 212, 217, 220, 221, 224, 225, 236, 244, 246, 247, 250, 252, 256, 268, 270, 272, 280, 282, 288
OFFSET
1,1
COMMENTS
Composite k such that A328390(k) <= A051903(k).
Composite k for which A051903(A327859(n)) <= A051903(k).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A051903(n) = if((1==n), 0, vecmax(factor(n)[, 2]));
A328114(n) = { my(s=0, p=2); while(n, s = max(s, (n%p)); n = n\p; p = nextprime(1+p)); (s); };
isA351099(n) = (n>1&&!isprime(n)&&(A328114(A003415(n)) <= A051903(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 03 2022
STATUS
approved
a(n) = 1 if the maximal digit in the primorial base representation of n' is less than the maximal exponent in the prime factorization of n, where n' stands for the arithmetic derivative of n, A003415.
+10
2
0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1
OFFSET
1
FORMULA
a(n) = [A328390(n) < A051903(n)], where [ ] is the Iverson bracket.
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A051903(n) = if((1==n), 0, vecmax(factor(n)[, 2]));
ismaxprimobasedigit_at_most(n, k) = { my(s=0, p=2); while(n, if((n%p)>k, return(0)); n = n\p; p = nextprime(1+p)); (1); };
A369637(n) = ((n>1) && ismaxprimobasedigit_at_most(A003415(n), A051903(n)-1));
CROSSREFS
Characteristic function of A351098.
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 01 2024
STATUS
approved

Search completed in 0.008 seconds