A285715 a(n) = A000120(A245611(n)).

0, 1, 2, 3, 1, 4, 5, 2, 6, 7, 3, 8, 2, 1, 9, 10, 4, 3, 11, 5, 12, 13, 2, 14, 3, 6, 15, 4, 7, 16, 17, 3, 5, 18, 8, 19, 20, 2, 4, 21, 1, 22, 6, 9, 23, 5, 10, 7, 24, 4, 25, 26, 3, 27, 28, 11, 29, 8, 5, 6, 4, 12, 2, 30, 13, 31, 7, 2, 32, 33, 14, 5, 9, 3, 34, 35, 6, 10, 36, 15, 8, 37, 4, 38, 5, 7, 39, 3, 16, 40, 41, 17, 11, 6, 3, 42, 43, 5, 44, 45, 18, 9, 12, 8, 7

Offset: 1

Author

Antti Karttunen, Apr 25 2017

Keywords

• nonn

Links

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

Crossrefs

Cf. A000120, A245611, A285712, A285714, A285716.

Cf. A007051 (positions of 0 and 1's).

Programs

Scheme

;; First implementation uses memoization-macro definec:
(definec (A285715 n) (if (<= n 2) (- n 1) (+ (if (= 2 (modulo n 3)) 0 1) (A285715 (A285712 n)))))
(define (A285715 n) (A000120 (A245611 n)))

Formula

a(1) = 0, a(2) = 1, for n > 2, a(n) = a(A285712(n)) + [n <> 2 mod 3]. (Where [] is Iverson bracket, giving here 1 if n is of the form 3k or 3k+1, and 0 if it is of the form 3k+2.)

a(n) = A000120(A245611(n)).