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 A286362 #10 Feb 16 2025 08:33:45 %S A286362 1,2,5,7,2,23,9,29,7,16,5,80,2,31,40,121,2,67,5,67,16,23,9,302,7,16, %T A286362 38,94,2,532,20,497,16,16,23,631,2,23,31,277,2,436,5,80,67,31,14,1178, %U A286362 7,67,23,67,2,302,31,328,16,16,5,1957,2,50,142,2017,16,436,5,67,16,467,9,2557,2,16,80,80,16,499,14,1129,121,16,5,1771,16,23,31,302,2,1771 %N A286362 Compound filter: a(n) = P(A089309(n), A046523(n)), where P(n,k) is sequence A000027 used as a pairing function. %C A286362 For all odd i, odd j: a(i) = a(j) <=> A286251(i) = A286251(j). %H A286362 Antti Karttunen, <a href="/A286362/b286362.txt">Table of n, a(n) for n = 1..16384</a> %H A286362 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PairingFunction.html">Pairing Function</a> %F A286362 a(n) = (1/2)*(2 + ((A089309(n)+A046523(n))^2) - A089309(n) - 3*A046523(n)). %o A286362 (Scheme) (define (A286362 n) (* (/ 1 2) (+ (expt (+ (A089309 n) (A046523 n)) 2) (- (A089309 n)) (- (* 3 (A046523 n))) 2))) %Y A286362 Cf. A000027, A046523, A089309, A286161, A286251, A286365. %K A286362 nonn %O A286362 1,2 %A A286362 _Antti Karttunen_, May 08 2017