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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, 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 (list; table; graph; refs; listen; history; text; internal format)
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 A153012

Adjacent sequences:  A128207 A128208 A128209 * A128211 A128212 A128213

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Feb 19 2007

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)