A115859 Largest 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, 19, 0, 9, 10, 15, 12, 21, 0, 27, 0, 0, 0, 31, 0, 29, 30, 35, 0, 25, 26, 27, 28, 0, 38, 27, 0, 17, 18, 0, 20, 45, 30, 51, 24, 25, 42, 55, 0, 45, 54, 59, 0, 0, 0, 63, 0, 61, 62, 67, 0, 57, 58, 71, 60, 69, 70, 63, 0

Offset

1,7

Comments

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

Links

Table of n, a(n) for n=1..80.

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

Crossrefs

a(2n) = 2*a(n). Bisection A115860 gives the terms at odd positions. Differs from A115869 for the first time at n=23, where a(23)=19, while A115869(23)=15. Cf. A115857, A115861, A115871.

Sequence in context: A369931 A160086 A115869 * A241663 A344976 A344876

Adjacent sequences: A115856 A115857 A115858 * A115860 A115861 A115862

Keyword

nonn

Author

Antti Karttunen, Feb 07 2006

Status

approved