A278506 Inverse permutation to A278505.

1, 2, 3, 4, 5, 7, 6, 11, 9, 16, 8, 22, 10, 29, 14, 37, 12, 46, 15, 56, 13, 67, 17, 79, 20, 92, 21, 106, 23, 121, 27, 137, 18, 154, 30, 172, 19, 191, 28, 211, 38, 232, 35, 254, 24, 277, 47, 301, 36, 326, 26, 352, 57, 379, 25, 407, 31, 436, 68, 466, 44, 497, 45, 529, 80, 562, 54, 596, 39, 631, 93, 667, 34, 704, 32

Offset

1,2

Links

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

Index entries for sequences that are permutations of the natural numbers

Formula

a(n) = (1/2) * ((c+r)^2 - r - 3*c + 2), where c = A278539(n), and r = A278538(n).

Prog

(Scheme) (define (A278506 n) (let ((row (A278538 n)) (col (A278539 n))) (* (/ 1 2) (- (expt (+ row col) 2) row col col col -2))))

Crossrefs

Inverse: A278505.

Cf. A278538, A278539.

Cf. also A278504, A278512.

Sequence in context: A266637 A370496 A278505 * A255546 A358874 A080688

Adjacent sequences: A278503 A278504 A278505 * A278507 A278508 A278509

Keyword

nonn

Author

Antti Karttunen, Nov 23 2016

Status

approved