%I A069780
%S A069780 1,2,2,1,2,4,2,2,1,4,2,2,2,4,4,1,2,2,2,2,4,4,2,8,1,4,2,2,2,8,2,2,4,4,4,
%T A069780 1,2,4,4,8,2,8,2,2,2,4,2,2,1,2,4,2,2,8,4,8,4,4,2,4,2,4,2,1,4,8,2,2,4,8,
%U A069780 2,2,2,4,2,2,4,8,2,2,1,4,2,4,4,4,4,8,2,4,4,2,4,4,4,4,2,2,2,1,2,8,2,8,8
%N A069780 a(n)=GCD[d(n^3),d(n)].
%F A069780 a(n)=GCD[A000005(n^3), A000005(n)]
%e A069780 Terms are usually powers of 2. Smallest number m such that A069780(m)=2^n
is A037992(n). The first n such that a(n) is not a power of 2 equals
432: a(432)=GCD[d[80621568],d[432]]=GCD[130,20]=10.
%t A069780 Table[GCD[DivisorSigma[0, n^3], DivisorSigma[0, n]], {n, 1, 500}]
%Y A069780 Cf. A000005, A037992, A069781, A069782.
%Y A069780 Sequence in context: A156260 A056671 A055076 this_sequence A066954 A144925
A029262
%Y A069780 Adjacent sequences: A069777 A069778 A069779 this_sequence A069781 A069782
A069783
%K A069780 easy,nonn
%O A069780 1,2
%A A069780 Labos E. (labos(AT)ana.sote.hu), Apr 08 2002
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