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 A324880 #10 Jul 20 2021 23:48:44 %S A324880 16,64,90,256,484,490,750,756,810,988,1000,1024,1296,1440,2116,2622, %T A324880 2662,3630,3710,4004,4116,4624,4896,4900,5880,6426,6724,6760,7290, %U A324880 7744,7840,7920,8100,8924,9604,10000 %N A324880 Even numbers k such that A324863(k) = A324874(k). %C A324880 Of 36 such numbers found in the range 1..10000, the following ten: 90, 490, 750, 810, 2622, 2662, 3630, 3710, 6426, 7290, are such that a positive integer of the form 4m+1 is produced when A156552 is applied to them: 45, 105, 117, 189, 225, 405, 765, 2205, 2565, 262185 (when sorted into ascending order). See also A324647. %H A324880 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a> %H A324880 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a> %H A324880 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %o A324880 (PARI) for(n=1,10000,if(!(n%2)&&A324863(n)==A324874(n), print1(n,", "))); %Y A324880 Cf. A156552, A323243, A324398, A324647, A324863, A324866, A324874. %Y A324880 Subsequence of A324879. %K A324880 nonn %O A324880 1,1 %A A324880 _Antti Karttunen_, Mar 27 2019