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 A277900 #13 Nov 14 2016 10:37:57 %S A277900 4,9,25,49,93,169,287,361,529,802,934,1333,1681,1754,2209,2809,2966, %T A277900 3482,4453,5041,5329,6241,5378,6374,9167 %N A277900 Column 2 of A277898; position of the second occurrence of n in A277892. %C A277900 a(n) = the second smallest number k for which A277892(k) = n, where A277892(n) = the number of prime divisors (counted with multiplicity) of A048675(n). %C A277900 Note that the sequence is not monotonic: a(22) = 6241 and a(23) = 5378. %F A277900 a(n) = A277893(A065091(n)). %F A277900 a(n) <= A001248(n). %e A277900 A277892[2..4] = [0, 1, 1], thus as the second 1 occurs at A277892(4), a(1) = 4. %e A277900 A277892[5..9] = [2, 1, 3, 1, 2], thus as the second 2 occurs at A277892(9), a(2) = 9. %o A277900 (Scheme) %o A277900 (define (A277900 n) (A277898bi n 2)) ;; Code for A277898bi given in A277898. %o A277900 (define (A277900 n) (A277893 (A065091 n))) ;; Alternatively. %Y A277900 Column 2 of A277898. %Y A277900 Cf. A001248 (an upper bound), A048675, A065091, A277892, A277893. %K A277900 nonn,more %O A277900 1,1 %A A277900 _Antti Karttunen_, Nov 08 2016, terms a(18)-a(25) obtained from the 10000 term b-file of A277892 computed by _Hans Havermann_