A140878 Nonzero entries in the array on page 8 of the reference.

1, 1, 1, 2, 3, 1, 1, 5, 11, 19, 10, 2, 1, 9, 37, 85, 158, 103, 35, 5, 1, 14, 87, 332, 782, 1521, 1126, 499, 126, 14, 1, 20, 172, 911, 3343, 8004, 16056, 12941, 6765, 2296, 462, 42, 1, 27, 305, 2096, 10147, 36350, 88044, 180621, 154750, 90781, 37178, 10254, 1716, 132

Offset

1,4

Comments

Terms shown are given (also) on page 11 of the reference. - Joerg Arndt, May 23 2021

Links

Table of n, a(n) for n=1..56.

Marko Petkovsek and Herbert S. Wilf, On a conjecture of Ira Gessel, arXiv:0807.3202 [math.CO], 2008.

Example

Table begins:
  1, 1;
  1, 2, 3, 1;
  1, 5, 11, 19, 10, 2;
  1, 9, 37, 85, 158, 103, 35, 5;
  1, 14, 87, 332, 782, 1521, 1126, 499, 126, 14;
  1, 20, 172, 911, 3343, 8004, 16056, 12941, 6765, 2296, 462, 42;
  1, 27, 305, 2096, 10147, 36350, 88044, 180621, 154750, 90781, 37178, 10254, 1716, 132;
  ...

Crossrefs

Sequence in context: A194680 A131739 A011151 * A182933 A342673 A365463

Adjacent sequences: A140875 A140876 A140877 * A140879 A140880 A140881

Keyword

nonn,tabf

Author

Jonathan Vos Post, Jul 22 2008

Status

approved