%I A091983
%S A091983 1,20,180,560,1460,2520,5040,6880,11700,15140,22680,26640,40880,43960,
%T A091983 61920,70560,93620,98280,136260,137200,183960,192640,239760,243360,
%U A091983 327600,315020,395640,408800,502240,487800,635040,595840,748980,745920
%N A091983 a(0) = 1, a(n) = 20*sigma[3](n).
%C A091983 G.f. A(x) satisfies 0=f(A(x),A(x^2),A(x^4)) where f(u,v,w)=u^2+33v^2+256w^2-18uv+16uw-288vw+220(v-w).
- Michael Somos, Jul 19 2004
%o A091983 (PARI) a(n)=if(n<1,n==0,20*sigma(n,3)) /* Michael Somos, Jul 19 2004
*/
%Y A091983 Sequence in context: A140044 A027332 A159538 this_sequence A037250 A000144
A047645
%Y A091983 Adjacent sequences: A091980 A091981 A091982 this_sequence A091984 A091985
A091986
%K A091983 nonn
%O A091983 0,2
%A A091983 N. J. A. Sloane (njas(AT)research.att.com), following a suggestion of
John McKay, Mar 19 2004
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