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Compound filter: a(n) = P(A061395(n), A286465(n)), where P(n,k) is sequence A000027 used as a pairing function.
2

%I #7 May 14 2017 15:54:58

%S 0,2,5,11,94,5,14,254,17,9,195,47,259,500,9,11,413,138,44,303,32,20,

%T 2784,47,354,216,5,329,506,9,77,3161,356,35,175,107,202,2709,216,24,

%U 11188,14,420,356,24,285,450,498,70,2349,35,51,115937,5,20,329,74,310,3420,864,1243,336,500,11,384,20,580,47285,87,14,615,498,1296,3015,9,74,3491,216

%N Compound filter: a(n) = P(A061395(n), A286465(n)), where P(n,k) is sequence A000027 used as a pairing function.

%H Antti Karttunen, <a href="/A286453/b286453.txt">Table of n, a(n) for n = 1..10000</a>

%H Indranil Ghosh, <a href="/A286453/a286453.txt">Python program to generate the sequence</a>

%F a(n) = (1/2)*(2 + ((A061395(n)+A286465(n))^2) - A061395(n) - 3*A286465(n)).

%o (Scheme) (define (A286453 n) (* (/ 1 2) (+ (expt (+ (A061395 n) (A286465 n)) 2) (- (A061395 n)) (- (* 3 (A286465 n))) 2)))

%Y Cf. A000027, A046523, A061395, A112049, A278223, A286356, A286372, A286452.

%K nonn

%O 1,2

%A _Antti Karttunen_, May 14 2017