A163331 - OEIS

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

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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