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A084612 Triangle, read by rows, where the n-th row lists the (2n+1) coefficients of (1+x-2x^2)^n. 3
1, 1, 1, -2, 1, 2, -3, -4, 4, 1, 3, -3, -11, 6, 12, -8, 1, 4, -2, -20, 1, 40, -8, -32, 16, 1, 5, 0, -30, -15, 81, 30, -120, 0, 80, -32, 1, 6, 3, -40, -45, 126, 141, -252, -180, 320, 48, -192, 64, 1, 7, 7, -49, -91, 161, 357, -363, -714, 644, 728, -784, -224, 448, -128, 1, 8, 12, -56, -154, 168, 700, -328, -1791, 656, 2800 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Paul D. Hanna, Table of n, a(n) for n = 0..1023

EXAMPLE

Triangle begins:

1;

1, 1, -2;

1, 2, -3, -4, 4;

1, 3, -3, -11, 6, 12, -8;

1, 4, -2, -20, 1, 40, -8, -32, 16;

1, 5, 0, -30, -15, 81, 30, -120, 0, 80, -32;

1, 6, 3, -40, -45, 126, 141, -252, -180, 320, 48, -192, 64;

1, 7, 7, -49, -91, 161, 357, -363, -714, 644, 728, -784, -224, 448, -128;

1, 8, 12, -56, -154, 168, 700, -328, -1791, 656, 2800, -1344, -2464, 1792, 768, -1024, 256; ...

PROG

(PARI) {T(n, k)=polcoeff((1+x-2*x^2)^n, k)}

for(n=0, 10, for(k=0, 2*n, print1(T(n, k), ", ")); print(""))

CROSSREFS

Cf. A002426, A084600-A084611, A084613-A084615.

Sequence in context: A134967 A320581 A240855 * A295164 A241419 A203108

Adjacent sequences:  A084609 A084610 A084611 * A084613 A084614 A084615

KEYWORD

sign,tabf

AUTHOR

Paul D. Hanna, Jun 01 2003

STATUS

approved

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Last modified August 26 00:35 EDT 2019. Contains 326324 sequences. (Running on oeis4.)