cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A339395 Number of partitions of n into an even number of nonprime parts.

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%I A339395 #5 Dec 02 2020 20:59:03
%S A339395 1,0,1,0,1,1,1,2,2,3,4,4,6,7,8,10,13,14,19,20,26,29,36,40,51,56,70,76,
%T A339395 96,105,129,143,172,192,231,254,308,339,402,447,529,586,691,764,896,
%U A339395 993,1159,1281,1493,1652,1912,2114,2445,2699,3110,3436,3939,4356,4982,5497,6280
%N A339395 Number of partitions of n into an even number of nonprime parts.
%H A339395 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A339395 G.f.: (1/2) * (Product_{k>=1} (1 - x^prime(k)) / (1 - x^k) + Product_{k>=1} (1 + x^prime(k)) / (1 + x^k)).
%F A339395 a(n) = (A002095(n) + A302236(n)) / 2.
%e A339395 a(9) = 3 because we have [8, 1], [6, 1, 1, 1] and [4, 1, 1, 1, 1, 1].
%t A339395 nmax = 60; CoefficientList[Series[(1/2) (Product[(1 - x^Prime[k])/(1 - x^k), {k, 1, nmax}] + Product[(1 + x^Prime[k])/(1 + x^k), {k, 1, nmax}]), {x, 0, nmax}], x]
%Y A339395 Cf. A002095, A018252, A027187, A184198, A302236, A339380, A339396.
%K A339395 nonn
%O A339395 0,8
%A A339395 _Ilya Gutkovskiy_, Dec 02 2020