A029638 Numbers in the (1,2)-Pascal triangle A029635 that are different from 1.

2, 2, 3, 2, 4, 5, 2, 5, 9, 7, 2, 6, 14, 16, 9, 2, 7, 20, 30, 25, 11, 2, 8, 27, 50, 55, 36, 13, 2, 9, 35, 77, 105, 91, 49, 15, 2, 10, 44, 112, 182, 196, 140, 64, 17, 2, 11, 54, 156, 294, 378, 336, 204, 81, 19, 2, 12, 65, 210, 450, 672, 714, 540, 285, 100, 21, 2, 13, 77, 275, 660, 1122

Offset

1,1

References

D. M. Bressoud, Proofs and Confirmations, Camb. Univ. Press, 1999; triangle on page 6, denominators.

Links

Table of n, a(n) for n=1..72.

Eric Weisstein's World of Mathematics, Alternating Sign Matrix.

D. Zeilberger, Dave Robbins's Art of Guessing, Adv. in Appl. Math. 34 (2005), 939-954.

Example

Triangle begins:
  2;
  3,  2;
  4,  5,  2;
  5,  9,  7,  2;
  6, 14, 16,  9,  2;
  7, 20, 30, 25, 11,  2;
  ...

Crossrefs

Cf. A048601, A029656.

Sequence in context: A033822 A368315 A144428 * A342297 A305820 A364934

Adjacent sequences: A029635 A029636 A029637 * A029639 A029640 A029641

Keyword

nonn,tabl,frac

Author

Mohammad K. Azarian

Extensions

More terms from David W. Wilson

Leading 2 inserted as consequence of change in A029635 by Sean A. Irvine, Mar 01 2020

Status

approved