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A104027 Triangle, read by rows, equal to the matrix inverse of A056241, which is formed from the even-indexed trinomial coefficients. 5
1, -1, 1, 2, -3, 1, -7, 12, -6, 1, 41, -73, 41, -10, 1, -376, 675, -390, 105, -15, 1, 5033, -9048, 5256, -1446, 225, -21, 1, -92821, 166901, -97034, 26796, -4242, 427, -28, 1, 2257166, -4058703, 2359939, -652054, 103515, -10570, 742, -36, 1, -69981919, 125837748, -73169550, 20218251, -3210939 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Column 0 forms signed Hammersley's polynomial p_n(1) (A006846). Column 1 forms A104028.

Triangle T(n,k), 0<=k<=n, read by rows, given by [ -1, -1, -3, -4, -7, -9, -13, -16, -21, ...] DELTA [1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, ...] where DELTA is the operator defined in A084938; see A004652 : 0, 1, 1, 3, 4, 7, 9, 13, ... - Philippe Deléham, Sep 26 2005

LINKS

Table of n, a(n) for n=0..49.

EXAMPLE

Rows begin:

1;

-1,1;

2,-3,1;

-7,12,-6,1;

41,-73,41,-10,1;

-376,675,-390,105,-15,1;

5033,-9048,5256,-1446,225,-21,1;

-92821,166901,-97034,26796,-4242,427,-28,1;

2257166,-4058703,2359939,-652054,103515,-10570,742,-36,1; ...

PROG

(PARI) T(n, k)=if(n<k || k<0, 0, ((matrix(n+2, n+2, m, j, if(m && gt; =j, polcoeff((1+x+x^2)^(m-1)+O(x^(2*j)), 2*j-2))))^-1)[n+1, k+1])

CROSSREFS

Cf. A056241, A104028, A027907.

Sequence in context: A050512 A107102 A103364 * A192363 A097710 A171024

Adjacent sequences:  A104024 A104025 A104026 * A104028 A104029 A104030

KEYWORD

sign,tabl

AUTHOR

Paul D. Hanna, Feb 26 2005

STATUS

approved

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Last modified June 14 15:36 EDT 2021. Contains 345025 sequences. (Running on oeis4.)