This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A144373 #11 May 09 2019 22:03:43 %S A144373 1,1,1,1,1,1,1,1,1,1,2,2,3,2,4,2,4,3,4,4,8,6,6,10,7,8,10,8,12,18,16, %T A144373 12,28,15,22,22,22,24,48,32,30,60,38,46,57,44,56,102,76,60,142,76,108, %U A144373 124,100,112,234,153,136,292,174,216,276,204,246,476,330,272,642,348,464 %N A144373 Shifts 9 places left under Dirichlet convolution. %H A144373 Alois P. Heinz, <a href="/A144373/b144373.txt">Table of n, a(n) for n = 1..1000</a> %H A144373 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %F A144373 G.f.: x + x^2 + x^3 + x^4 + x^5 + x^6 + x^7 + x^8 + x^9 * (1 + Sum_{i>=1} Sum_{j>=1} a(i)*a(j)*x^(i*j)). - _Ilya Gutkovskiy_, May 09 2019 %p A144373 k:= 9: 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 A144373 9th column of A144374. Cf. A000005. %K A144373 eigen,nonn %O A144373 1,11 %A A144373 _Alois P. Heinz_, Sep 18 2008