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 A331858 #30 Feb 06 2020 03:27:55
%S A331858 42,1316,475664,131080256,8783210218496,2250975213522944,
%T A331858 147570574898545885184,37778715690312487141376,
%U A331858 2475879193127080196116054016,41538374636164863806350357434466304,10633823951424046514111736193740701696,178405961584350762488394070192754827810832384
%N A331858 a(n) = (2^p-1)*(2^(p-1))*((2^p-1)^2-2), where p is the n-th prime.
%C A331858 Integers a(1), a(2), a(4), a(8) corresponding to p = 2, 3, 7, 19 are also terms of A331805. - _Bernard Schott_, Feb 04 2020
%F A331858 a(n) = A060286(n)*A093112(prime(n)). - _M. F. Hasler_, Jan 31 2020
%t A331858 f[p_] := (2^p-1)*(2^(p-1))*((2^p-1)^2-2); f @ Prime @ Range[12] (* _Amiram Eldar_, Jan 29 2020 *)
%o A331858 (PARI) [(2^p-1)*((2^p-1)^2-2)<<(p-1) | p<-primes(12)] \\ or: a(n,p=prime(n))={...}. - _M. F. Hasler_, Jan 29 2020
%Y A331858 Cf. A000040 (primes), A000396 (perfect numbers), A093112 ((2^n-1)^2-2), A060286 (2^(p-1)*(2^p-1)), A331805.
%K A331858 nonn,easy
%O A331858 1,1
%A A331858 _G. L. Honaker, Jr._, Jan 29 2020