A115869 Smallest natural number m < n, such that there exists nonzero solutions to a cross-domain congruence m*i = n X i, zero if no such integer exists.

0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 7, 0, 5, 6, 0, 0, 0, 0, 15, 0, 13, 14, 15, 0, 9, 10, 15, 12, 13, 0, 11, 0, 0, 0, 31, 0, 29, 30, 35, 0, 25, 26, 27, 28, 0, 30, 23, 0, 17, 18, 0, 20, 45, 30, 19, 24, 25, 26, 23, 0, 21, 22, 27, 0, 0, 0, 63, 0, 61, 62, 63, 0, 57, 58, 59, 60, 61, 70, 55, 0

Offset: 1

Author

Antti Karttunen, Feb 07 2006

Keywords

• nonn

Comments

Here * stands for ordinary multiplication and X means carryless (GF(2)[X]) multiplication (A048720).

Links

• Index entries for sequences defined by congruent products between domains N and GF(2)[X]

Crossrefs

a(2n) = 2*a(n). Bisection A115870 gives the terms at odd positions. Differs from A115859 for the first time at n=23, where a(23)=15, while A115859(23)=19. Cf. A115857, A115861, A115871.