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 A365960 #40 Dec 21 2024 21:25:15
%S A365960 27,38,40,48,56,64,54,78,86,72,100,84,114,96,128,108,142,120,126,162,
%T A365960 138,176,150,156,196,168,174,216,186,192,236,204,210,256,222,228,234,
%U A365960 282,246,252,302,264,270,276,328,288,294,300,354,312,318,324,380,336,342,348,406,360,366,372,378,438,390,396,402
%N A365960 Sum of the 6 nearest neighbors of n in a hexagonal spiral with positive integers.
%H A365960 Eric Angelini, <a href="https://cinquantesignes.blogspot.com/2023/09/an-hexagonal-seq.html">An hexagonal seq?</a>, Personal blog "Cinquante signes", Sept 2023.
%H A365960 Eric Angelini, <a href="/A365960/a365960.pdf">An hexagonal seq?</a>, Personal blog "Cinquante signes", Sept 2023 [Cached copy]
%e A365960 Spiral begins:
%e A365960 49--48--47--46--45
%e A365960 / \
%e A365960 50 28--27--26--25 44
%e A365960 / / \ \
%e A365960 51 29 13--12--11 24 43
%e A365960 / / / \ \ \
%e A365960 52 30 14 4---3 10 23 42
%e A365960 / / / / \ \ \ \
%e A365960 53 31 15 5 1---2 9 22 41
%e A365960 \ \ \ \ / / /
%e A365960 54 32 16 6---7---8 21 40
%e A365960 \ \ \ / /
%e A365960 55 33 17--18--19--20 39
%e A365960 \ \ /
%e A365960 56 34--35--36--37--38
%e A365960 \
%e A365960 57--58--59--60--61
%e A365960 .
%e A365960 The 6 nearest neighbors of 2 are 1,3,7,8,9,10. Their sum is a(2)=38.
%t A365960 step=9; ta[x_]:=Table[12,x];f=Flatten[Table[Table[{ta[If[m==2,k-1,k]],16+2m+12k},{m,6}],{k,0,step}]][[3;;]];Join[{27,38},f+6Range[3,Length@f+2]]
%Y A365960 Cf. A214176, A278181, A278619.
%K A365960 nonn
%O A365960 1,1
%A A365960 _Eric Angelini_ and _Giorgos Kalogeropoulos_, Sep 23 2023