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 A067758 #21 Jun 19 2022 02:19:05 %S A067758 1,4,9,27,42,60,64,70,78,144,168,180,216,238,260,318,558,600,672,960, %T A067758 1008,1053,1260,1620,1806,2112,3318,3780,4608,5544,12152,40084,40095, %U A067758 41664,47040,48825,49176,51870,59832,60528,71040,99008,100356,113904,132000,159000 %N A067758 Numbers k such that sigma(prime(k) - 1) == 0 (mod k). %C A067758 There are 91 terms up to and including 10 million. - _Harvey P. Dale_, Oct 04 2016 %H A067758 Amiram Eldar, <a href="/A067758/b067758.txt">Table of n, a(n) for n = 1..163</a> (terms 1..91 from Harvey P. Dale) %t A067758 Select[Range[120000],Divisible[DivisorSigma[1,Prime[#]-1],#]&] (* _Harvey P. Dale_, Oct 04 2016 *) %o A067758 (PARI) for(k=1,120000, if(sigma(prime(k)-1)%k==0,print1(k,","))) %Y A067758 Cf. A000203, A006093, A008332. %K A067758 nonn %O A067758 1,2 %A A067758 _Benoit Cloitre_, Feb 05 2002 %E A067758 More terms from _Klaus Brockhaus_, Feb 07 2002