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A128207 Number triangle T(n,k)=(-1)^(n-k)*[k<=n]*Product{i=1..n,Sum{j=0..i-1,F(j-1)}/Product{i=1..k,Sum{j=0..i-1,F(j-1)}}. 1
1, -1, 1, 1, -1, 1, -2, 2, -2, 1, 6, -6, 6, -3, 1, -30, 30, -30, 15, -5, 1, 240, -240, 240, -120, 40, -8, 1, -3120, 3120, -3120, 1560, -520, 104, -13, 1, 65520, -65520, 65520, -32760, 10920 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,7

COMMENTS

First two subdiagonals are -A000045(n+1) and A001654(n+1). Inverse is A128206.

LINKS

Table of n, a(n) for n=0..40.

EXAMPLE

Triangle begins

1,

-1, 1,

1, -1, 1,

-2, 2, -2, 1,

6, -6, 6, -3, 1,

-30, 30, -30, 15, -5, 1,

240, -240, 240, -120, 40, -8, 1,

-3120, 3120, -3120, 1560, -520, 104, -13, 1,

65520, -65520, 65520, -32760, 10920, -2184, 273, -21, 1

CROSSREFS

Sequence in context: A255399 A181830 A086612 * A306707 A180958 A295854

Adjacent sequences:  A128204 A128205 A128206 * A128208 A128209 A128210

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Feb 19 2007

STATUS

approved

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Last modified October 14 04:44 EDT 2019. Contains 327995 sequences. (Running on oeis4.)