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

Author

Alford Arnold, Oct 23 2004

Keywords

• nonn
• tabf

Examples

			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.