%I A019565
%S A019565 1,2,3,6,5,10,15,30,7,14,21,42,35,70,105,210,11,22,33,66,55,110,165,
%T A019565 330,77,154,231,462,385,770,1155,2310,13,26,39,78,65,130,195,390,91,
%U A019565 182,273,546,455,910,1365,2730,143,286,429,858,715,1430,2145,4290
%N A019565 If n = Sum 2^e_i, e_i distinct, then a(n) = Product prime_{e_{i+1}}.
%F A019565 G.f. prod(k>=0, 1 + prime(k+1)*x^2^k), where prime(k)=A000040(k). - Ralf
Stephan (ralf(AT)ark.in-berlin.de), Jun 20 2003
%t A019565 Do[m=1;o=1;k1=k;While[ k1>0, k2=Mod[k1, 2];If[k2\[Equal]1, m=m*Prime[o]];
k1=(k1-k2)/ 2;o=o+1];Print[m], {k, 0, 55}] (Lei Zhou (lzhou5(AT)emory.edu),
Feb 15 2005)
%Y A019565 Sequence in context: A055944 A073740 A077320 this_sequence A133477 A039653
A106379
%Y A019565 Adjacent sequences: A019562 A019563 A019564 this_sequence A019566 A019567
A019568
%K A019565 nonn
%O A019565 0,2
%A A019565 Marc LeBrun (mlb(AT)well.com)
|