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, 156, 55, 11, 1, 15, 126, 357, 504, 414, 210, 66, 12, 1

Offset

0,6

Links

Andrew Howroyd, Table of n, a(n) for n = 0..883 (rows 0..50)

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}.

Prog

(PARI) T(n)=[Vecrev(p/y^valuation(p, y)) | p<-Vec(1/(1-x*y*(1+x+x^2)) + O(x*x^n))]
{ my(A=T(12)); for(i=1, #A, print(A[i])) } \\ Andrew Howroyd, Oct 04 2025

Crossrefs

Cf. A000073, A027907, A071675, A098925.

Sequence in context: A229742 A126572 A162910 * A309213 A377433 A371103

Adjacent sequences: A098972 A098973 A098974 * A098976 A098977 A098978

Keyword

nonn,tabf

Author

Alford Arnold, Oct 23 2004

Status

approved