Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
A065546
a(n) is smallest prime > 2*a(n-1), a(1) = 13.
2
13, 29, 59, 127, 257, 521, 1049, 2099, 4201, 8419, 16843, 33703, 67409, 134837, 269683, 539389, 1078787, 2157587, 4315183, 8630387, 17260781, 34521589, 69043189, 138086407, 276172823, 552345671, 1104691373, 2209382761
OFFSET
1,1
LINKS
MATHEMATICA
NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 13; a[n_] := NextPrim[ 2*a[n - 1]]; Table[ a[n], {n, 1, 35} ]
NestList[NextPrime[2#]&, 13, 30] (* Harvey P. Dale, Feb 25 2015 *)
PROG
(PARI) { for (n=1, 200, if (n>1, a=nextprime(2*a), a=13); write("b065546.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 21 2009
CROSSREFS
Sequence in context: A094481 A045637 A146743 * A075636 A139838 A217197
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Nov 28 2001
STATUS
approved