A172381 Triangle whose inverse has production matrix with general term (-1)^(n-k+1)*C(k+1, n-k+1).

1, 1, 1, 2, 3, 1, 5, 10, 6, 1, 14, 36, 31, 10, 1, 42, 137, 156, 75, 15, 1, 132, 544, 787, 510, 155, 21, 1, 429, 2235, 4017, 3331, 1380, 287, 28, 1, 1430, 9445, 20809, 21405, 11411, 3255, 490, 36, 1, 4862, 40876, 109486, 136921, 90665, 33390, 6916, 786, 45, 1, 16796

Offset

0,4

Comments

Product of A033184 and A172380. Diagonal sums are A172382(n+2).

Links

Table of n, a(n) for n=0..55.

Example

Triangle begins
1,
1, 1,
2, 3, 1,
5, 10, 6, 1,
14, 36, 31, 10, 1,
42, 137, 156, 75, 15, 1,
132, 544, 787, 510, 155, 21, 1,
429, 2235, 4017, 3331, 1380, 287, 28, 1,
1430, 9445, 20809, 21405, 11411, 3255, 490, 36, 1,
4862, 40876, 109486, 136921, 90665, 33390, 6916, 786, 45, 1,
16796, 180544, 584955, 877252, 704720, 322728, 86443, 13536, 1200, 55, 1
Production array of inverse is
-1, 1,
0, -2, 1,
0, 1, -3, 1,
0, 0, 3, -4, 1,
0, 0, -1, 6, -5, 1,
0, 0, 0, -4, 10, -6, 1,
0, 0, 0, 1, -10, 15, -7, 1,
0, 0, 0, 0, 5, -20, 21, -8, 1,
0, 0, 0, 0, -1, 15, -35, 28, -9, 1,
0, 0, 0, 0, 0, -6, 35, -56, 36, -10, 1,
0, 0, 0, 0, 0, 1, -21, 70, -84, 45, -11, 1

Crossrefs

Sequence in context: A105640 A090299 A060693 * A089302 A049020 A299105

Adjacent sequences: A172378 A172379 A172380 * A172382 A172383 A172384

Keyword

nonn,tabl

Author

Paul Barry, Feb 01 2010

Status

approved