A243500 Self-inverse permutation of natural numbers: a(2n) = A003961(A048673(n)), a(2n-1) = 2 * A245448(n).

2, 1, 4, 3, 6, 5, 8, 7, 10, 9, 22, 27, 20, 15, 14, 33, 18, 17, 28, 13, 34, 11, 62, 29, 26, 25, 12, 19, 24, 75, 68, 43, 16, 21, 46, 69, 118, 45, 82, 243, 142, 99, 32, 63, 38, 35, 78, 171, 50, 49, 52, 51, 116, 275, 74, 147, 122, 81, 60, 59, 88, 23, 44, 201, 66, 65, 98, 31, 36

Offset

1,1

Links

Antti Karttunen, Table of n, a(n) for n = 1..8192

Index entries for sequences that are permutations of the natural numbers

Formula

a(2n) = A003961(A048673(n)), a(2n-1) = 2 * A245448(n).

a(2n) = A003961(A048673(n)), a(2n-1) = A243502(A064989(2n-1)).

a(2n) = A003961((A003961(n)+1)/2), a(2n-1) = 2 * A064216(A064989(2n-1)).

Prog

(Scheme, two alternative implementations)
(define (A243500 n) (cond ((odd? n) (A243502 (A064989 n))) (else (A003961 (A048673 (/ n 2))))))
(define (A243500 n) (if (even? n) (A003961 (A048673 (/ n 2))) (* 2 (A245448 (/ (1+ n) 2)))))

Crossrefs

Cf. A003961, A048673, A064989, A243502, A244319, A245448.

Sequence in context: A163501 A306229 A096779 * A026262 A026234 A352726

Adjacent sequences: A243497 A243498 A243499 * A243501 A243502 A243503

Keyword

nonn

Author

Antti Karttunen, Jul 18 2014

Status

approved