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 A167301 #12 Oct 19 2023 02:16:00 %S A167301 1,0,9,0,27,0,45,0,81,0,81,0,99,0,243,0,135,0,153,0,405,0,189,0,729,0, %T A167301 729,0,243,0,261,0,729,0,1215,0,315,0,891,0,351,0,369,0,2187,0,405,0, %U A167301 2025,0,1215,0,459,0,2187,0,1377,0,513,0,531,0,3645,0,2673,0 %N A167301 Totally multiplicative sequence with a(p) = 9*(p-2) for prime p. %H A167301 G. C. Greubel, <a href="/A167301/b167301.txt">Table of n, a(n) for n = 1..1000</a> %F A167301 Multiplicative with a(p^e) = (9*(p-2))^e. If n = Product p(k)^e(k) then a(n) = Product (9*(p(k)-2))^e(k). %F A167301 a(2k) = 0 for k >= 1. %F A167301 a(n) = A165830(n) * A166586(n) = 9^bigomega(n) * A166586(n) = 9^A001222(n) * A166586(n). %t A167301 a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((fi[[All, 1]] - 2)^fi[[All, 2]])); Table[a[n]*9^PrimeOmega[n], {n, 1, 100}] (* _G. C. Greubel_, Jun 07 2016 *) %t A167301 f[p_, e_] := (9*(p-2))^e; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* _Amiram Eldar_, Oct 19 2023 *) %Y A167301 Cf. A001222, A165830, A166586. %K A167301 nonn,easy,mult %O A167301 1,3 %A A167301 _Jaroslav Krizek_, Nov 01 2009