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A136237
Matrix cube of triangle V = A136230, read by rows.
2
1, 6, 1, 54, 15, 1, 629, 225, 24, 1, 9003, 3770, 504, 33, 1, 153276, 71655, 10988, 891, 42, 1, 3031553, 1539315, 259236, 23903, 1386, 51, 1, 68406990, 37072448, 6688092, 672672, 44135, 1989, 60, 1, 1736020806, 992226060, 188767184, 20225436, 1442049
OFFSET
0,2
FORMULA
Column k of V^3 (this triangle) = column 2 of P^(3k+2), where P = triangle A136220.
EXAMPLE
This triangle, V^3, begins:
1;
6, 1;
54, 15, 1;
629, 225, 24, 1;
9003, 3770, 504, 33, 1;
153276, 71655, 10988, 891, 42, 1;
3031553, 1539315, 259236, 23903, 1386, 51, 1;
68406990, 37072448, 6688092, 672672, 44135, 1989, 60, 1;
1736020806, 992226060, 188767184, 20225436, 1442049, 73304, 2700, 69, 1;
where column 0 of V^3 = column 2 of P^2 = triangle A136225.
PROG
(PARI) {T(n, k)=local(P=Mat(1), U=Mat(1), V=Mat(1), PShR); if(n>0, for(i=0, n, PShR=matrix(#P, #P, r, c, if(r>=c, if(r==c, 1, if(c==1, 0, P[r-1, c-1])))); U=P*PShR^2; V=P^2*PShR; U=matrix(#P+1, #P+1, r, c, if(r>=c, if(r<#P+1, U[r, c], if(c==1, (P^3)[ #P, 1], (P^(3*c-1))[r-c+1, 1])))); V=matrix(#P+1, #P+1, r, c, if(r>=c, if(r<#P+1, V[r, c], if(c==1, (P^3)[ #P, 1], (P^(3*c-2))[r-c+1, 1])))); P=matrix(#U, #U, r, c, if(r>=c, if(r<#R, P[r, c], (U^c)[r-c+1, 1]))))); (V^3)[n+1, k+1]}
CROSSREFS
Cf. related tables: A136220 (P), A136228 (U), A136230 (V), A136231 (W=P^3), A136234 (V^2).
Sequence in context: A113387 A290316 A090435 * A308281 A347211 A083837
KEYWORD
nonn,tabl
AUTHOR
Paul D. Hanna, Feb 07 2008
STATUS
approved