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A108086 Triangle, read by rows, where T(0,0) = 1, T(n,k) = (-1)^(n+k)*T(n-1,k) + T(n-1,k-1); a signed version of Pascal's triangle. 0
1, -1, 1, -1, -2, 1, 1, -3, -3, 1, 1, 4, -6, -4, 1, -1, 5, 10, -10, -5, 1, -1, -6, 15, 20, -15, -6, 1, 1, -7, -21, 35, 35, -21, -7, 1, 1, 8, -28, -56, 70, 56, -28, -8, 1, -1, 9, 36, -84, -126, 126, 84, -36, -9, 1, -1, -10, 45, 120, -210, -252, 210, 120, -45, -10, 1, 1, -11, -55, 165, 330, -462, -462, 330, 165, -55, -11, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Row sums are 1,0,-2,-4,-4,0,8,16,16,0,-32,-64,-64,0,128,256,256,... Antidiagonal sums are 1,-1,0,-1,-1,0,-1,1,0,1,1,0,1,-1,0,-1,-1,0,-1,1,0,1...

LINKS

Table of n, a(n) for n=0..77.

FORMULA

a(n, k) = (-1)^(int((n-k+1)/2)*A007318(n, k) (A007318 is Pascal's triangle).

CROSSREFS

Cf. A007318, A009116, A090132.

Sequence in context: A118433 A007318 * A130595 A108363 A076831 A197061

Adjacent sequences:  A108083 A108084 A108085 * A108087 A108088 A108089

KEYWORD

sign,tabl

AUTHOR

Gerald McGarvey, Jun 05 2005

STATUS

approved

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Last modified October 17 21:44 EDT 2018. Contains 316293 sequences. (Running on oeis4.)