A093315 Number of permutations s_1,s_2,...,s_n of 1,2,...,n with s_1 = 4 and such that for all j=1,2,...,n, s_j divides Sum_{i=1..j} s_i.

0, 0, 0, 1, 2, 2, 2, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 6, 8, 3, 14, 12, 18, 13, 14, 6, 26, 13, 198, 152, 220, 118, 1033, 807

Offset

1,5

Comments

The beginning elements of the permutation are 4, (either 1 or 2), ...

The total number of permutations with this property is given in A067957.

Links

Table of n, a(n) for n=1..40.

Matthijs Coster, Sequences

Matthijs Coster, Problem 2001/3-A of the Universitaire Wiskunde Competitie, Nieuw Arch. Wisk. 5/3 (2002), 92-94.

Crossrefs

Cf. A067957, A093313, A093315.

Sequence in context: A076953 A180472 A308583 * A204267 A237452 A132784

Adjacent sequences: A093312 A093313 A093314 * A093316 A093317 A093318

Keyword

nonn,more

Author

Matthijs Coster, Apr 26 2004

Status

approved