A260429 Column index to A255545: if n is Lucky number, then a(n) = 1, otherwise a(n) = 1 + the position at the stage where n is removed in the Lucky sieve.

1, 2, 1, 3, 2, 4, 1, 5, 1, 6, 3, 7, 1, 8, 1, 9, 4, 10, 2, 11, 1, 12, 5, 13, 1, 14, 2, 15, 6, 16, 1, 17, 1, 18, 7, 19, 1, 20, 3, 21, 8, 22, 1, 23, 2, 24, 9, 25, 1, 26, 1, 27, 10, 28, 2, 29, 3, 30, 11, 31, 4, 32, 1, 33, 12, 34, 1, 35, 1, 36, 13, 37, 1, 38, 1, 39, 14, 40, 1, 41, 5, 42, 15, 43, 2, 44, 1, 45, 16, 46, 4, 47, 1, 48, 17, 49, 3, 50, 1, 51, 18, 52, 6, 53, 1

Offset

1,2

Links

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

Formula

Other identities. For all n >= 1:

a(n) = 1 + A260437(n).

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

a(2n) = n+1. [Even numbers are removed at the stage one of the sieve, after 1 which is also removed in the beginning.]

a(A219178(n)) = 2.

A255545(A260438(n), a(n)) = n.

Prog

(Scheme)
(define (A260429 n) (cond ((not (zero? (A145649 n))) 1) ((even? n) (+ 1 (/ n 2))) (else (let searchrow ((row 2)) (let searchcol ((col 1)) (cond ((>= (A255543bi row col) n) (if (= (A255543bi row col) n) (+ 1 col) (searchrow (+ 1 row)))) (else (searchcol (+ 1 col))))))))) ;; Code for A255543bi given in A255543.

Crossrefs

One more than A260437.

Cf. A000959, A050505, A145649, A219178, A255543, A255545.

Cf. also A260438 (corresponding row index).

Cf. A078898, A246277, A260439, A260739 for column indices to other arrays similar to A255545.

Sequence in context: A124223 A295908 A300980 * A094193 A278539 A335880

Adjacent sequences: A260426 A260427 A260428 * A260430 A260431 A260432

Keyword

nonn

Author

Antti Karttunen, Jul 29 2015

Status

approved