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 A086352 #5 Dec 29 2023 10:26:41 %S A086352 1,2,10,74,740,9354,143144,2573586,53180944,1242078802,32358633632, %T A086352 930370449370,29264294868544,999646208968666,36852747307934336, %U A086352 1458402092927302178,61665517131334975744,2774522039432235946914 %N A086352 Main diagonal of square array A086350. %F A086352 a(n) = ((1+sqrt(2))*(n+sqrt(2))^n-(1-sqrt(2))*(n-sqrt(2))^n)/sqrt(8). %Y A086352 Cf. A000169, A086350. %K A086352 easy,nonn %O A086352 0,2 %A A086352 _Paul Barry_, Jul 18 2003