login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A046063
Numbers k such that the k-th partition number A000041(k) is prime.
50
2, 3, 4, 5, 6, 13, 36, 77, 132, 157, 168, 186, 188, 212, 216, 302, 366, 417, 440, 491, 498, 525, 546, 658, 735, 753, 825, 841, 863, 1085, 1086, 1296, 1477, 1578, 1586, 1621, 1793, 2051, 2136, 2493, 2502, 2508, 2568, 2633, 2727, 2732, 2871, 2912, 3027, 3098, 3168, 3342, 3542, 3641, 4118
OFFSET
1,1
COMMENTS
The corresponding primes are given in A049575. - Joerg Arndt, May 09 2013
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..4967 (contains all terms below 10^8)
Chris K. Caldwell, Top twenty prime partition numbers, The Prime Pages.
G. K. Patil, Ramanujan's Life And His Contributions In The Field Of Mathematics, International Journal of Scientific Research and Engineering Studies (IJSRES), Volume 1(6) (2014), ISSN: 2349-8862.
Eric Weisstein's World of Mathematics, Partition Function P Congruences.
Eric Weisstein's World of Mathematics, Partition Function P.
Eric Weisstein's World of Mathematics, Integer Sequence Primes.
MATHEMATICA
Select[ Range@3341, PrimeQ@ PartitionsP@# &] (* Robert G. Wilson v *)
PROG
(PARI) for(n=0, 10^5, my(p=numbpart(n)); if(isprime(p), print1(n, ", "))); \\ Joerg Arndt, May 09 2013
(Python)
from sympy import isprime, npartitions
print([n for n in range(1, 5001) if isprime(npartitions(n))]) # Indranil Ghosh, Apr 10 2017
KEYWORD
nonn,nice
EXTENSIONS
b-file extended by Max Alekseyev, Jul 07 2009, Jun 14 2011, Jan 08 2012, May 19 2014
STATUS
approved