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%I #9 May 09 2019 22:03:32
%S 1,1,1,1,1,1,1,1,2,2,3,2,4,2,4,5,6,6,8,8,6,10,13,12,18,16,22,14,26,26,
%T 32,37,40,48,34,52,66,64,86,86,108,70,125,132,144,180,194,216,158,250,
%U 290,300,386,388,472,317,540,592,640,772,836,950,668,1096,1236,1280
%N Shifts 7 places left under Dirichlet convolution.
%H Alois P. Heinz, <a href="/A144371/b144371.txt">Table of n, a(n) for n = 1..1000</a>
%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F G.f.: x + x^2 + x^3 + x^4 + x^5 + x^6 + x^7 * (1 + Sum_{i>=1} Sum_{j>=1} a(i)*a(j)*x^(i*j)). - _Ilya Gutkovskiy_, May 09 2019
%p k:= 7: with (numtheory): dck:= proc(b,c) proc(n, k) option remember; add (b(d,k) *c(n/d,k), d=`if`(n<0,{}, divisors(n))) end end: B:= dck(T,T): T:= (n, k)-> if n<=k then 1 else B(n-k, k) fi: a:= n-> T(n,k): seq (a(n), n=1..80);
%Y 7th column of A144374. Cf. A000005.
%K eigen,nonn
%O 1,9
%A _Alois P. Heinz_, Sep 18 2008
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