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Rectangular table where column k equals row sums of matrix power A078121^k, read by antidiagonals.
13

%I #14 Mar 17 2023 21:26:24

%S 1,1,1,1,2,1,1,4,3,1,1,10,9,4,1,1,36,35,16,5,1,1,202,201,84,25,6,1,1,

%T 1828,1827,656,165,36,7,1,1,27338,27337,8148,1625,286,49,8,1,1,692004,

%U 692003,167568,25509,3396,455,64,9,1,1,30251722,30251721,5866452,664665,64350,6321,680,81,10,1

%N Rectangular table where column k equals row sums of matrix power A078121^k, read by antidiagonals.

%C Determinant of n X n upper left submatrix is 2^[n(n-1)(n-2)/6] (see A125791). Related to partitions of numbers into powers of 2 (see A078121). Triangle A078121 shifts left one column under matrix square.

%H G. Blom and C.-E. Froeberg, <a href="/A002575/a002575.pdf">Om myntvaexling (On money-changing) [Swedish]</a>, Nordisk Matematisk Tidskrift, 10 (1962), 55-69, 103. [Annotated scanned copy] See Table 5.

%F T(n,k) = T(n,k-1) + T(n-1,2*k) for n>0, k>0, with T(0,n)=T(n,0)=1 for n>=0.

%e Recurrence T(n,k) = T(n,k-1) + T(n-1,2*k) is illustrated by:

%e T(4,3) = T(4,2) + T(3,6) = 201 + 455 = 656;

%e T(5,3) = T(5,2) + T(4,6) = 1827 + 6321 = 8148;

%e T(6,3) = T(6,2) + T(5,6) = 27337 + 140231 = 167568.

%e Rows of this table begin:

%e 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...;

%e 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, ...;

%e 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, ...;

%e 1, 10, 35, 84, 165, 286, 455, 680, 969, 1330, 1771, 2300, ...;

%e 1, 36, 201, 656, 1625, 3396, 6321, 10816, 17361, 26500, 38841, ...;

%e 1, 202, 1827, 8148, 25509, 64350, 140231, 274856, 497097, ...;

%e 1, 1828, 27337, 167568, 664665, 2026564, 5174449, 11622976, ...;

%e 1, 27338, 692003, 5866452, 29559717, 109082974, 326603719, ...;

%e 1, 692004, 30251721, 356855440, 2290267225, 10243585092, ...; ...

%e Triangle A078121 begins:

%e 1;

%e 1, 1;

%e 1, 2, 1;

%e 1, 4, 4, 1;

%e 1, 10, 16, 8, 1;

%e 1, 36, 84, 64, 16, 1;

%e 1, 202, 656, 680, 256, 32, 1; ...

%e where row sums form column 1 of this table A125790,

%e and column k of A078121 equals column 2^k-1 of this table A125790.

%e Matrix cube A078121^3 begins:

%e 1;

%e 3, 1;

%e 9, 6, 1;

%e 35, 36, 12, 1;

%e 201, 286, 144, 24, 1;

%e 1827, 3396, 2300, 576, 48, 1; ...

%e where row sums form column 3 of this table A125790,

%e and column 0 of A078121^3 forms column 2 of this table A125790.

%t T[n_, k_] := T[n, k] = T[n, k-1] + T[n-1, 2*k]; T[0, _] = T[_, 0] = 1; Table[T[n-k, k], {n, 0, 10}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Jun 15 2015 *)

%o (PARI) {T(n,k,p=0,q=2)=local(A=Mat(1), B); if(n<p||p<0, 0, for(m=1, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i||j==1, B[i, j]=1, B[i, j]=(A^q)[i-1, j-1]); )); A=B); return((A^(k+1))[n+1, p+1]))}

%o for(n=0,10,for(k=0,10,print1(T(n,k),", ")); print(""))

%Y Cf. A078121; A002577; A125791; columns: A002577, A125792, A125793, A125794, A125795, A125796; diagonals: A125797, A125798; A125799 (antidiagonal sums); related table: A125800 (q=3).

%K nonn,tabl

%O 0,5

%A _Paul D. Hanna_, Dec 10 2006, corrected Dec 12 2006