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%I #7 Feb 23 2019 22:09:44
%S 0,1,1,1,1,2,1,2,3,2,3,4,3,5,5,5,6,7,6,8,9,8,11,11,11,13,14,14,16,19,
%T 17,21,22,22,25,27,27,30,33,32,36,39,38,44,46,46,51,54,54,59,64,62,70,
%U 73,73,80,84,85,92,98,97,107,111,112,122,127,128,139,144,146,157,164,165,179
%N Number of partitions of n into powers of two minus one where every part appears at least 2 times.
%H R. H. Hardin, <a href="/A161064/b161064.txt">Table of n, a(n) for n = 1..1000</a>
%F G.f.: Product_{j>=1} (1 + x^(2*(2^j-1))/(1-x^(2^j-1))). - _Emeric Deutsch_, Jun 28 2009
%e a(16)=5 because we have 7711, 33331111, 3331^7, 331^(10), and 1^(16). - _Emeric Deutsch_, Jun 28 2009
%p g := product(1+x^(2*(2^j-1))/(1-x^(2^j-1)), j = 1 .. 20): gser := series(g, x = 0, 80): seq(coeff(gser, x, n), n = 1 .. 74); # _Emeric Deutsch_, Jun 28 2009
%K nonn
%O 1,6
%A _R. H. Hardin_, Jun 02 2009