A286362 - OEIS

A286362

Compound filter: a(n) = P(A089309(n), A046523(n)), where P(n,k) is sequence A000027 used as a pairing function.

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, 38, 94, 2, 532, 20, 497, 16, 16, 23, 631, 2, 23, 31, 277, 2, 436, 5, 80, 67, 31, 14, 1178, 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

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OFFSET

1,2

COMMENTS

For all odd i, odd j: a(i) = a(j) <=> A286251(i) = A286251(j).

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

Eric Weisstein's World of Mathematics, Pairing Function

FORMULA

a(n) = (1/2)*(2 + ((A089309(n)+A046523(n))^2) - A089309(n) - 3*A046523(n)).

PROG

(Scheme) (define (A286362 n) (* (/ 1 2) (+ (expt (+ (A089309 n) (A046523 n)) 2) (- (A089309 n)) (- (* 3 (A046523 n))) 2)))