A098975 Nonzero elements of table A071675; also counts selected ordered multisets of the values {1,2,3}.

1, 1, 1, 1, 1, 2, 1, 3, 3, 1, 2, 6, 4, 1, 1, 7, 10, 5, 1, 6, 16, 15, 6, 1, 3, 19, 30, 21, 7, 1, 1, 16, 45, 50, 28, 8, 1, 10, 51, 90, 77, 36, 9, 1, 4, 45, 126, 161, 112, 45, 10, 1, 1, 30, 141, 266, 266

Offset

0,6

Links

Table of n, a(n) for n=0..56.

Example

Shift A027907 as indicated and construct a(n) by column. The table begins
1
. 1 1 1
. . 1 2 3 2 1
. . . 1 3 6 7 6 3 1
. . . . 1 4 10 16 19 16 10 4 1
. . . . . 1 5 15 30 45 51 45 30 15 5 1
. . . . . . 1
therefore a(19) = 6 and appears in column seven and row three. a(19) counts the ordered multisets {133,313,331,223,232,322).

Crossrefs

Cf. A000073, A027907, A071675, A098925.

Sequence in context: A229742 A126572 A162910 * A309213 A371103 A127121

Adjacent sequences: A098972 A098973 A098974 * A098976 A098977 A098978

Keyword

nonn

Author

Alford Arnold, Oct 23 2004

Status

approved