A260437 Column index to A255543: if n is Lucky number then a(n) = 0, otherwise a(n) = the position at the stage where n is removed in the Lucky sieve.

0, 1, 0, 2, 1, 3, 0, 4, 0, 5, 2, 6, 0, 7, 0, 8, 3, 9, 1, 10, 0, 11, 4, 12, 0, 13, 1, 14, 5, 15, 0, 16, 0, 17, 6, 18, 0, 19, 2, 20, 7, 21, 0, 22, 1, 23, 8, 24, 0, 25, 0, 26, 9, 27, 1, 28, 2, 29, 10, 30, 3, 31, 0, 32, 11, 33, 0, 34, 0, 35, 12, 36, 0, 37, 0, 38, 13, 39, 0, 40, 4, 41, 14, 42, 1, 43, 0, 44, 15, 45, 3, 46, 0, 47, 16, 48, 2, 49, 0, 50, 17, 51, 5, 52

Offset: 1

Author

Antti Karttunen, Aug 02 2015

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10003

Crossrefs

One less than A260429.

Cf. A000959, A050505, A145649, A219178, A255543.

Cf. also A260438 (corresponding row index).

Programs

Scheme

(define (A260437 n) (cond ((not (zero? (A145649 n))) 0) ((even? n) (/ n 2)) (else (let searchrow ((row 2)) (let searchcol ((col 1)) (cond ((>= (A255543bi row col) n) (if (= (A255543bi row col) n) col (searchrow (+ 1 row)))) (else (searchcol (+ 1 col))))))))) ;; Code for A255543bi given in A255543.

Formula

Other identities. For all n >= 1:

a(n) = A260429(n) - 1.

Iff A145649(n) = 1, then a(n) = 0.

a(2n) = n.

a(A219178(n)) = 1.

A255543(A260438(A050505(n)), a(A050505(n))) = A050505(n).