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A304393 Expansion of Product_{k>0} (1 + Sum_{m>=0} x^(k*2^m)). 1

%I

%S 1,1,2,2,5,5,8,10,17,19,27,33,48,56,76,92,126,146,192,228,298,352,444,

%T 528,667,783,969,1145,1414,1658,2017,2365,2878,3352,4027,4703,5634,

%U 6548,7773,9033,10705,12381,14573,16857,19790,22800,26631,30655,35723,41005

%N Expansion of Product_{k>0} (1 + Sum_{m>=0} x^(k*2^m)).

%C Also the number of partitions of n in which each part occurs a power of 2 (cf. A000079) of times.

%H Vaclav Kotesovec, <a href="/A304393/b304393.txt">Table of n, a(n) for n = 0..10000</a> (terms 0..1000 from Seiichi Manyama)

%e n | Partitions of n in which each part occurs a power of 2 (cf. A000079) of times

%e --+------------------------------------------------------------------------------

%e 1 | 1;

%e 2 | 2 = 1+1;

%e 3 | 3 = 2+1;

%e 4 | 4 = 3+1 = 2+2 = 2+1+1 = 1+1+1+1;

%e 5 | 5 = 4+1 = 3+2 = 3+1+1 = 2+2+1;

%e 6 | 6 = 5+1 = 4+2 = 4+1+1 = 3+2+1 = 3+3 = 2+2+1+1 = 2+1+1+1+1;

%e 7 | 7 = 6+1 = 5+2 = 5+1+1 = 4+3 = 4+2+1 = 3+3+1 = 3+2+2 = 3+2+1+1 = 3+1+1+1+1;

%p b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,

%p b(n, i-1)+add(b(n-i*2^j, i-1), j=0..ilog2(n/i))))

%p end:

%p a:= n-> b(n$2):

%p seq(a(n), n=0..60); # _Alois P. Heinz_, May 13 2018

%Y Cf. A000079, A055922, A300446, A304332.

%K nonn

%O 0,3

%A _Seiichi Manyama_, May 12 2018

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Last modified May 26 02:56 EDT 2020. Contains 334613 sequences. (Running on oeis4.)