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 A072344 #7 Aug 23 2017 06:06:35
%S A072344 1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,1,1,1,2,1,1,1,2,2,1,1,1,1,2,1,1,2,1,
%T A072344 3,1,1,1,3,1,1,1,1,2,3,1,1,1,1,2,3,3,1,1,1,3,1,1,1,1,1,1,1,3,2,2,1,3,
%U A072344 2,3,1,3,1,1,1,1,1,3,1,3,2,1,1,3,3,1,2,1,1,3,1,2,1,1,1,3,1,1,1,1,1,3,1,2,2
%N A072344 a(n) = the least natural number k such that k*phi(n) + 1 is prime.
%H A072344 Antti Karttunen, <a href="/A072344/b072344.txt">Table of n, a(n) for n = 1..10000</a>
%F A072344 a(n) = A034693(A000010(n)). - _Antti Karttunen_, Aug 22 2017
%e A072344 phi(35) = 24 and the least natural number k such that 24 k + 1 is prime is k = 3; so a(35) = 3.
%t A072344 f[n_] := Module[{i}, i = 0; While[ ! PrimeQ[i*EulerPhi[n] + 1], i++ ]; i]; Table[f[i], {i, 1, 150}]
%o A072344 (PARI)
%o A072344 A034693(n) = { my(k=1); while(!isprime(1+(k*n)), k++); k; };
%o A072344 A072344(n) = A034693(eulerphi(n)); \\ _Antti Karttunen_, Aug 22 2017
%Y A072344 Cf. A000010, A034693, A072917.
%K A072344 nonn
%O A072344 1,15
%A A072344 _Joseph L. Pe_, Jul 16 2002