A271420 Nonludicity of n.

0, 0, 0, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 3, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 4, 1, 2, 1, 3, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 3, 1, 2, 1, 0, 1, 5, 1, 2, 1, 4, 1, 0, 1, 2, 1, 3, 1, 0, 1, 2, 1, 0, 1, 6, 1, 2, 1, 0, 1, 3, 1, 2, 1, 0, 1, 4, 1

Offset: 1

Author

Max Barrentine, Apr 07 2016

Keywords

• nonn

Comments

If n is ludic, a(n)=0; if n is nonludic, a(n) is the step at which n is rejected from the ludic number sieve.

Links

• Max Barrentine, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A003309, A192490, A192607, A255127, A271419.

Cf. A265859 (analogous version for lucky numbers).

Programs

Scheme

(define (A271419 n) (* (- 1 (A192490 n)) (A260738 n))) ;; Antti Karttunen, Sep 11 2016

Formula

a(n) = (1-A192490(n)) * A260738(n). - Antti Karttunen, Sep 11 2016