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A252752
Inverse permutation to sequence A246278 when it is considered as a permutation of natural numbers (with assumption that a(1) = 1).
5
1, 2, 4, 3, 7, 5, 11, 8, 6, 12, 16, 17, 22, 23, 9, 30, 29, 38, 37, 47, 18, 57, 46, 68, 10, 80, 13, 93, 56, 107, 67, 122, 31, 138, 14, 155, 79, 173, 69, 192, 92, 212, 106, 233, 24, 255, 121, 278, 15, 302, 94, 327, 137, 353, 25, 380, 156, 408, 154, 437, 172, 467, 58, 498, 40, 530, 191, 563, 193, 597, 211, 632, 232, 668, 48, 705, 20
OFFSET
1,2
FORMULA
a(1) = 1; for n>1: a(n) = 1 + A246276(n-1).
As a composition of related permutations:
a(n) = A253562(A122111(n)).
a(n) = 1 + A253552(A156552(n)).
PROG
(Scheme, two versions)
(define (A252752 n) (if (<= n 1) n (let ((x (A055396 n)) (y (A246277 n))) (+ 1 (* (/ 1 2) (- (expt (+ x y) 2) x y y y -2))))))
(define (A252752 n) (if (<= n 1) n (+ 1 (A246276 (- n 1)))))
CROSSREFS
Inverse of array A246278 considered as a permutation of natural numbers with prepended a(1) = 1.
Related permutations A122111, A156552, A246276, A253552, A253562.
Differs from A252460 for the first time at n=21, where a(21) = 18, while A252460(21) = 13.
Sequence in context: A365231 A255128 A252460 * A056536 A258237 A361939
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 03 2015
STATUS
approved