login
a(n) is the number of partitions of n into parts not greater than A020639(n).
2

%I #18 Sep 05 2018 08:12:35

%S 1,2,3,3,7,4,15,5,12,6,56,7,101,8,27,9,297,10,490,11,48,12,1255,13,

%T 377,14,75,15,4565,16,6842,17,108,18,1115,19,21637,20,147,21,44583,22,

%U 63261,23,192,24,124754,25,16475,26,243,27,329931,28,5260,29,300,30,831820,31

%N a(n) is the number of partitions of n into parts not greater than A020639(n).

%C a(n) = A000041(n) iff n=1 or n is prime. [corrected by _Robert Israel_, Sep 04 2018]

%C a(2*n) = n+1.

%H Robert Israel, <a href="/A097359/b097359.txt">Table of n, a(n) for n = 1..10000</a>

%p f:= n -> combinat:-numbpart(n, min(numtheory:-factorset(n))):

%p f(1):= 1:

%p map(f, [$1..100]); # _Robert Israel_, Sep 04 2018

%Y Cf. A000041, A020639, A097360.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Aug 09 2004