login
A144631
Second diagonal (or column) of A144630.
2
4, 12, 880, 46900, 1615824, 45094896, 1115345088, 25519125060, 553014576400, 11514200107696, 232490008680384, 4581732884262352, 88532684825838400, 1683073282734360000, 31561148509363526400, 584964180982546208100
OFFSET
2,1
LINKS
MAPLE
invH := proc(n, i, j) (-1)^(i+j)*(i+j-1)*binomial(n+i-1, n-j)*binomial(n+j-1, n-i)* (binomial(i+j-2, i-1))^2 ; end: A144630 := proc(n, k) local T, i, j ; T := 0 ; for i from n-k+1 to n do for j from n-k+1 to n do T := T+invH(n, i, j) ; od; od; RETURN(T) ; end: A144631 := proc(n) A144630(n+1, 2) ; end: for n from 1 to 20 do printf("%a, ", A144631(n)) : od: # R. J. Mathar, Jan 21 2009
PROG
(Magma) [ [ &+[I[i][j]: i, j in [k..n] ]: k in [n..1 by -1] ][2] where I:=H^-1 where H:=Matrix(Rationals(), n, n, [ < i, j, 1/(i+j-1) >: i, j in [1..n] ] ): n in [2..17] ]; // Klaus Brockhaus, Jan 22 2009
CROSSREFS
Sequence in context: A299808 A085116 A104129 * A009516 A266500 A146210
KEYWORD
nonn
AUTHOR
Daniel McLaury and Ben Golub, Jan 20 2009
EXTENSIONS
More terms from R. J. Mathar and Klaus Brockhaus, Jan 21 2009
STATUS
approved