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 A137174 #4 Oct 27 2020 14:50:51
%S A137174 0,6,4,25,-13,37,-25,49,73,-98,146,-49,-73,97,121,36,-218,266,-109,
%T A137174 -133,314,-133,193,229,-350,-193,217,-205,229,1241,-1169,289,-530,
%U A137174 1168,-1144,626,36,-301,361,36,-698,1504,-1480,397,-385,2069,144,-1708,-445,469
%N A137174 First differences of A138383.
%t A137174 Differences[Join[{3},(#[[2]]-#[[1]]) (Total[#]+1)/2&/@Partition[Prime[ Range[ 60]],2,1]]] (* _Harvey P. Dale_, Oct 27 2020 *)
%Y A137174 Cf. A138383.
%K A137174 easy,sign
%O A137174 1,2
%A A137174 _Odimar Fabeny_, May 11 2008
%E A137174 More terms from _Harvey P. Dale_, Oct 27 2020