A286593 Compound filter (the length of rightmost run of 1's in base-2 & deficiency/abundance): a(n) = P(A089309(n), A286449(n)), where P(n,k) is sequence A000027 used as a pairing function.

1, 1, 5, 1, 4, 12, 24, 1, 16, 2, 30, 38, 37, 13, 32, 1, 46, 56, 80, 79, 22, 107, 139, 138, 137, 22, 173, 18, 172, 175, 281, 1, 67, 154, 122, 211, 232, 57, 139, 254, 277, 121, 327, 8, 37, 381, 439, 408, 407, 436, 212, 11, 466, 138, 564, 598, 562, 596, 668, 784, 704, 258, 196, 1, 352, 121, 782, 22, 301, 38, 864, 821, 862, 562, 632, 47, 631, 156, 1039, 947, 407

Offset

1,3

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Pairing Function

Formula

a(n) = (1/2)*(2 + ((A089309(n)+A286449(n))^2) - A089309(n) - 3*A286449(n)).

Prog

(Scheme) (define (A286593 n) (* (/ 1 2) (+ (expt (+ (A089309 n) (A286449 n)) 2) (- (A089309 n)) (- (* 3 (A286449 n))) 2)))

Crossrefs

Cf. A000027, A033879, A033880, A089309, A286449, A286592, A286595.

Sequence in context: A011301 A316248 A180132 * A242376 A307393 A231923

Adjacent sequences: A286590 A286591 A286592 * A286594 A286595 A286596

Keyword

nonn

Author

Antti Karttunen, May 21 2017

Status

approved