A128210 Number triangle T(n,k)=(-1)^(n-k)*[k<=n]*Product{i=1..n,Sum{j=0..i-1,A078008(j-1)}/Product{i=1..k,Sum{j=0..i-1,A078008(j-1)}}.

1, -1, 1, 1, -1, 1, -3, 3, -3, 1, 15, -15, 15, -5, 1, -165, 165, -165, 55, -11, 1, 3465, -3465, 3465, -1155, 231, -21, 1, -148995, 148995, -148995, 49665, -9933, 903, -43, 1, 12664575, -12664575, 12664575

Offset

0,7

Comments

Inverse is A128208. Sub-diagonals include -A001045(n+1) and A084175(n+1).

Links

Table of n, a(n) for n=0..38.

Example

Triangle begins
1,
-1, 1,
1, -1, 1,
-3, 3, -3, 1,
15, -15, 15, -5, 1,
-165, 165, -165, 55, -11, 1,
3465, -3465, 3465, -1155, 231, -21, 1,
-148995, 148995, -148995, 49665, -9933, 903, -43, 1

Crossrefs

Sequence in context: A155969 A076237 A201432 * A215409 A239232 A346624

Adjacent sequences: A128207 A128208 A128209 * A128211 A128212 A128213

Keyword

easy,sign,tabl

Author

Paul Barry, Feb 19 2007

Status

approved