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A218380 Number of partitions of n into distinct pentagonal parts. 9

%I

%S 1,1,0,0,0,1,1,0,0,0,0,0,1,1,0,0,0,1,1,0,0,0,1,1,0,0,0,1,1,0,0,0,0,0,

%T 1,2,1,0,0,1,2,1,0,0,0,0,0,1,1,0,0,1,2,1,0,0,1,2,1,0,0,0,1,2,1,0,0,0,

%U 1,2,2,1,0,1,2,2,1,0,1,1,0,0,1,1,0,1,2,2

%N Number of partitions of n into distinct pentagonal parts.

%H Seiichi Manyama, <a href="/A218380/b218380.txt">Table of n, a(n) for n = 0..10000</a> (terms 1..100 from Antonio Roldán)

%e A(98)=3 because 98 = 12 + 35 + 51 = 1 + 5 + 92 = 1 + 5 + 22 + 70 with 1, 5, 22, 70, 92 pentagonal numbers.

%o (PARI){ for (n=1, 100, m=polcoeff(prod(k=1, truncate(1+sqrt(24*n+1))/6, 1+x^(k*(3*k-1)/2)), n);write("B218380.txt",n, " ",m)) }

%Y Cf. A000326, A218379, A290942.

%K nonn

%O 0,36

%A _Antonio Roldán_, Oct 27 2012

%E a(0) = 1 prepended by _Seiichi Manyama_, Dec 09 2017

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Last modified October 18 21:24 EDT 2021. Contains 348070 sequences. (Running on oeis4.)