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A128254 Erroneous version of A103450. 2
1, 1, 1, 1, 3, 1, 1, 5, 5, 1, 1, 7, 12, 7, 1, 1, 9, 22, 22, 9, 1, 1, 11, 35, 50, 35, 11, 11, 13, 51, 95, 95, 51, 13, 1, 1, 15, 70, 161, 210, 161, 70, 15, 1, 1, 17, 92, 252, 406, 406, 252, 92, 17, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

The triangle is bisymmetric, row sums = A045623: (1, 2, 5, 12, 28, 64,...). A114219(signed) * A007318 = A128255.

LINKS

Table of n, a(n) for n=1..54.

FORMULA

A007318 * A114219, where the latter is signed: {1; 0,1; 0,1,1; 0,-1,2,1; 0,1,-2,3,1;...}. The signed version of A114219 = A097807 * A128229.

T(n,k) = k Binomial[n-2,k-1] + Binomial[n-2,k-2], for 1 <= k <= n. - O. D'Antona, Dec 17 2007

EXAMPLE

First few rows of the triangle are:

1;

1, 1;

1, 3, 1;

1, 5, 5, 1;

1, 7, 12, 7, 1;

1, 9, 22, 22, 9, 1;

1, 11, 35, 50, 35, 11, 1;

...

Central coefficients T(2n,n) = A141222. - Emanuele Munarini, Jun 01 2012

PROG

(Maxima) T(n, k):=k*binomial(n-2, k-1)+binomial(n-2, k-2);

create_list(T(n+1, k+1), n, 0, 30, k, 0, n); [Emanuele Munarini, Jun 01 2012]

CROSSREFS

Cf. A128229, A007318, A114219, A128255, A045623, A141222.

Sequence in context: A109128 A113245 A103450 * A277930 A026714 A008288

Adjacent sequences:  A128251 A128252 A128253 * A128255 A128256 A128257

KEYWORD

dead

AUTHOR

Gary W. Adamson, Feb 20 2007

EXTENSIONS

Typo in sequence corrected by O. D'Antona (dantona(AT)dico.unimi.it), Dec 17 2007

STATUS

approved

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Last modified October 19 16:17 EDT 2019. Contains 328223 sequences. (Running on oeis4.)