A163331 Inverse permutation to A163330.

0, 2, 5, 1, 4, 8, 3, 7, 12, 9, 14, 20, 13, 19, 26, 18, 25, 33, 27, 35, 44, 34, 43, 53, 42, 52, 63, 6, 11, 17, 10, 16, 23, 15, 22, 30, 24, 32, 41, 31, 40, 50, 39, 49, 60, 51, 62, 74, 61, 73, 86, 72, 85, 99, 21, 29, 38, 28, 37, 47, 36, 46, 57, 48, 59, 71, 58, 70, 83, 69, 82, 96

Offset

0,2

Links

A. Karttunen, Table of n, a(n) for n = 0..6560

Index entries for sequences that are permutations of the natural numbers

Formula

a(n) = A001477bi(A163326(n),A163325(n)), where A001477bi(x,y) = (((x+y)^2)+x+(3y))/2.

Prog

(Scheme:) (define (A163331 n) (A001477bi (A163326 n) (A163325 n)))
(define (A001477bi x y) (/ (+ (expt (+ x y) 2) x (* 3 y)) 2))

Crossrefs

Inverse: A163330. a(n) = A163329(A163327(n)). Cf. A007089.

Sequence in context: A034005 A340407 A161688 * A011034 A191332 A229982

Adjacent sequences: A163328 A163329 A163330 * A163332 A163333 A163334

Keyword

nonn,base

Author

Antti Karttunen, Jul 29 2009

Status

approved