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A114158 Triangle, read by rows, equal to the matrix inverse of Q=A113381. 8
1, -2, 1, 4, -5, 1, 21, -5, -8, 1, 130, 20, -32, -11, 1, 1106, 840, -260, -77, -14, 1, 10044, 24865, -2584, -1089, -140, -17, 1, -18366, 823383, -12828, -21428, -2737, -221, -20, 1, -9321125, 31847653, 1160956, -523831, -73458, -5474, -320, -23, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..44.

EXAMPLE

Triangle Q^-1 begins:

1;

-2,1;

4,-5,1;

21,-5,-8,1;

130,20,-32,-11,1;

1106,840,-260,-77,-14,1;

10044,24865,-2584,-1089,-140,-17,1;

-18366,823383,-12828,-21428,-2737,-221,-20,1; ...

Triangle Q^-2 begins:

1;

-4,1;

18,-10,1;

20,30,-16,1;

-139,255,24,-22,1;

-3945,3085,544,0,-28,1;

-99849,51015,12444,671,-42,-34,1; ...

PROG

(PARI) T(n, k)=local(P, Q, R, W); P=Mat(1); for(m=2, n+1, W=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3 || j==i || j>m-1, W[i, j]=1, if(j==1, W[i, 1]=1, W[i, j]=(P^(3*j-2))[i-j+1, 1])); )); P=W); Q=matrix(#P, #P, r, c, if(r>=c, (P^(3*c-1))[r-c+1, 1])); (Q^-1)[n+1, k+1]

CROSSREFS

Cf. A113370 (P), A113381 (Q), A113389 (R); A114150 (R^2*Q^-1=Q^3*P^-2), A114151 (R^-2*Q^3=Q^-1*P^2), A114152 (R^3*P^-1), A114153 (R^-1*P^3), A114154 (R^3*Q^-2), A114155 (Q^-2*P^3); A114156 (P^-1), A114159 (R^-1).

Sequence in context: A137346 A264017 A159971 * A248666 A162407 A352458

Adjacent sequences: A114155 A114156 A114157 * A114159 A114160 A114161

KEYWORD

sign,tabl

AUTHOR

Paul D. Hanna, Nov 15 2005

STATUS

approved

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Last modified January 27 05:08 EST 2023. Contains 359836 sequences. (Running on oeis4.)