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A114150 Triangle, read by rows, given by the product R^2*Q^-1 = Q^3*P^-2 using triangular matrices P=A113370, Q=A113381, R=A113389. 9
1, 4, 1, 28, 7, 1, 326, 91, 10, 1, 5702, 1722, 190, 13, 1, 136724, 43764, 4945, 325, 16, 1, 4226334, 1415799, 163705, 10751, 496, 19, 1, 161385532, 56096733, 6617605, 437723, 19896, 703, 22, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Complementary to A114151, which gives R^-2*Q^3 = Q^-1*P^2.

LINKS

Table of n, a(n) for n=0..35.

EXAMPLE

Triangle R^2*Q^-1 = Q^3*P^-2 begins:

1;

4,1;

28,7,1;

326,91,10,1;

5702,1722,190,13,1;

136724,43764,4945,325,16,1;

4226334,1415799,163705,10751,496,19,1; ...

Compare to P (A113370):

1;

1,1;

1,4,1;

1,28,7,1;

1,326,91,10,1;

1,5702,1722,190,13,1; ...

Thus R^2*Q^-1 = Q^3*P^-2 equals P shift left one column.

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])); R=matrix(#P, #P, r, c, if(r>=c, (P^(3*c))[r-c+1, 1])); (R^2*Q^-1)[n+1, k+1]

CROSSREFS

Cf. A113370 (P), A113381 (Q), A113389 (R); 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), A114158 (Q^-1), A114159 (R^-1).

Sequence in context: A134151 A264773 A119304 * A134149 A035469 A290598

Adjacent sequences: A114147 A114148 A114149 * A114151 A114152 A114153

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna, Nov 15 2005

STATUS

approved

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Last modified February 26 20:36 EST 2023. Contains 360676 sequences. (Running on oeis4.)