A351085 - OEIS

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A351085

Lexicographically earliest infinite sequence such that a(i) = a(j) => A327858(i) = A327858(j) and A345000(i) = A345000(j) for all i, j >= 0.

1, 2, 3, 3, 4, 3, 5, 3, 6, 7, 3, 3, 4, 3, 8, 2, 9, 3, 10, 3, 11, 12, 3, 3, 13, 12, 14, 8, 4, 3, 3, 3, 15, 16, 3, 17, 18, 3, 19, 2, 4, 3, 3, 3, 6, 8, 20, 3, 21, 16, 14, 12, 22, 3, 10, 2, 4, 2, 3, 3, 4, 3, 8, 8, 23, 24, 3, 3, 11, 2, 3, 3, 25, 3, 8, 26, 27, 24, 3, 3, 9, 7, 3, 3, 4, 2, 14, 2, 28, 3, 10, 2, 29, 2, 30

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OFFSET

0,2

COMMENTS

Restricted growth sequence transform of the ordered pair [A327858(n), A345000(n)].

For all i, j >= 1: A305800(i) = A305800(j) => a(i) = a(j).

For all i, j >= 0: a(i) = a(j) => A351086(i) = A351086(j).

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..65537

PROG

(PARI)

up_to = 65537;

rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };

A003415(n) = {my(fac); if(n<1, 0, fac=factor(n); sum(i=1, matsize(fac)[1], n*fac[i, 2]/fac[i, 1]))}; \\ From A003415

A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };

A327858(n) = gcd(A003415(n), A276086(n));

A345000(n) = gcd(A003415(n), A003415(A276086(n)));

Aux351085(n) = [A327858(n), A345000(n)];

v351085 = rgs_transform(vector(1+up_to, n, Aux351085(n-1)));

A351085(n) = v351085[1+n];

CROSSREFS

Cf. A003415, A276086, A327858, A345000, A351086.

Cf. also A305800, A351080.

Sequence in context: A053475 A140605 A350064 * A049878 A038203 A255239

Adjacent sequences: A351082 A351083 A351084 * A351086 A351087 A351088

KEYWORD

nonn,easy,look

AUTHOR

Antti Karttunen, Feb 03 2022

STATUS

approved