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 A273822 #31 Jul 18 2025 14:44:51 %S A273822 27,227,335,2387,9299,104571,113519,118499,212343,258999,328499, %T A273822 455600,699891,820755,971360,977051,1059239,1119723,1193631,1421367, %U A273822 1604084,2231999,2794067,4191431,5450948,6054611,6769607,7672391,7760639,7875035,8091615,9606203,15511268 %N A273822 Integers k such that k^3 + 1 is the average of two positive cubes. %H A273822 Chai Wah Wu, <a href="/A273822/b273822.txt">Table of n, a(n) for n = 1..44</a> %e A273822 27 is a term because 27^3 + 1 = (4^3 + 34^3)/2. %o A273822 (PARI) isA003325(n) = for(k=1, sqrtnint(n\2, 3), ispower(n-k^3, 3) && return(1)); %o A273822 lista(nn) = for(n=1, nn, if(isA003325(2*(n^3+1)), print1(n, ", "))); %Y A273822 Cf. A001093, A003325. %K A273822 nonn %O A273822 1,1 %A A273822 _Altug Alkan_, May 31 2016 %E A273822 a(9)-a(12) from _Giovanni Resta_, Jun 01 2016 %E A273822 a(13)-a(33) from _Chai Wah Wu_, Jun 19 2016