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A185690 Exponential Riordan array (1,sin(x)). 2
1, 0, 1, -1, 0, 1, 0, -4, 0, 1, 1, 0, -10, 0, 1, 0, 16, 0, -20, 0, 1, -1, 0, 91, 0, -35, 0, 1, 0, -64, 0, 336, 0, -56, 0, 1, 1, 0, -820, 0, 966, 0, -84, 0, 1, 0, 256, 0, -5440, 0, 2352, 0, -120, 0, 1, -1, 0, 7381, 0, -24970, 0, 5082, 0, -165, 0, 1, 0, -1024, 0, 87296, 0, -90112, 0, 10032, 0, -220, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

The row n=0 with T(0,0)=1 and the column T(n,0)=0, n>0, are not entered into the sequence here.

A signed version of A136630 (apart from row 0 and column 0). - Peter Bala, Oct 06 2011

LINKS

Table of n, a(n) for n=1..78.

Vladimir Kruchinin, Composition of ordinary generating functions, arXiv:1009.2565

FORMULA

T(n,k)= 2^(1-k)/k! *sum{i=0..floor(k/2)} (-1)^(floor((n+k)/2)-i) *binomial(k,i) *(2*i-k)^n, for even(n-k).

EXAMPLE

1;

0,1;

-1,0,1;

0,-4,0,1;

1,0,-10,0,1;

0,16,0,-20,0,1;

-1,0,91,0,-35,0,1;

0,-64,0,336,0,-56,0,1;

MAPLE

A185690 := proc(n, k) if type(k+n, 'even') then 2^(1-k)/k! * add( (-1)^(floor((n+k)/2)-i)*binomial(k, i)*(2*i-k)^n, i=0..floor(k/2)) ; else 0; end if; end proc: # R. J. Mathar, Feb 21 2011

MATHEMATICA

t[n_, k_] /; OddQ[n - k] = 0; t[n_, k_] /; EvenQ[n - k] := 2^(1-k)/k!* Sum[ (-1)^(Floor[(n+k)/2] - i)*Binomial[k, i]*(2*i-k)^n, {i, 0, k/2}]; Table[t[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* Jean-François Alcover, Feb 21 2013 *)

CROSSREFS

Cf. A136630.

Sequence in context: A006838 A061309 A059064 * A096459 A218453 A186372

Adjacent sequences:  A185687 A185688 A185689 * A185691 A185692 A185693

KEYWORD

sign,tabl

AUTHOR

Vladimir Kruchinin, Feb 10 2011

STATUS

approved

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Last modified May 18 15:48 EDT 2013. Contains 225422 sequences.