cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-1 of 1 results.

A236961 Triangle, read by rows, that transforms diagonals in the table of coefficients in the successive iterations of g.f. of A236960 such that column 0 equals T(n,0) = n^n.

Original entry on oeis.org

1, 1, 1, 4, 2, 1, 27, 11, 3, 1, 256, 94, 21, 4, 1, 3125, 1076, 217, 34, 5, 1, 46656, 15362, 2910, 412, 50, 6, 1, 823543, 262171, 47598, 6333, 695, 69, 7, 1, 16777216, 5198778, 915221, 116768, 12045, 1082, 91, 8, 1, 387420489, 117368024, 20182962, 2498414, 247151, 20871, 1589, 116, 9, 1, 10000000000
Offset: 0

Views

Author

Paul D. Hanna, Feb 01 2014

Keywords

Examples

			This triangle begins:
1;
1, 1;
4, 2, 1;
27, 11, 3, 1;
256, 94, 21, 4, 1;
3125, 1076, 217, 34, 5, 1;
46656, 15362, 2910, 412, 50, 6, 1;
823543, 262171, 47598, 6333, 695, 69, 7, 1;
16777216, 5198778, 915221, 116768, 12045, 1082, 91, 8, 1;
387420489, 117368024, 20182962, 2498414, 247151, 20871, 1589, 116, 9, 1;
10000000000, 2970653234, 501463686, 60678776, 5824330, 471666, 33761, 2232, 144, 10, 1; ...
in which column 0 equals T(n,0) = n^n.
ILLUSTRATION.
This triangle transforms diagonals in the table of coefficients in the iterations of G(x), the g.f. of A236960, that starts as:
G(x) = x + x^2 + 2*x^3 + 5*x^4 + 16*x^5 + 79*x^6 + 720*x^7 + 10735*x^8 + 211802*x^9 + 4968491*x^10 + 132655760*x^11 + 3943593218*x^12 +...
The table of coefficients in the successive iterations of G(x) begins:
[1,  0,   0,    0,     0,      0,       0,        0,         0, ...];
[1,  1,   2,    5,    16,     79,     720,    10735,    211802, ...];
[1,  2,   6,   21,    84,    410,    2876,    33235,    581074, ...];
[1,  3,  12,   54,   266,   1463,    9740,    90999,   1308954, ...];
[1,  4,  20,  110,   648,   4102,   28932,   248808,   2972926, ...];
[1,  5,  30,  195,  1340,   9705,   75264,   655599,   7059436, ...];
[1,  6,  42,  315,  2476,  20284,  174304,  1610487,  16952240, ...];
[1,  7,  56,  476,  4214,  38605,  366660,  3656975,  39586868, ...];
[1,  8,  72,  684,  6736,  68308,  712984,  7710392,  88021908, ...];
[1,  9,  90,  945, 10248, 114027, 1299696, 15223599, 185218134, ...];
[1, 10, 110, 1265, 14980, 181510, 2245428, 28396003, 369356822, ...]; ...
Then this triangle T transforms the adjacent diagonals in the above table into each other, as illustrated by:
T*[1, 1,  6,  54,  648,  9705, 174304, 3656975,  88021908, ...]
= [1, 2, 12, 110, 1340, 20284, 366660, 7710392, 185218134, ...];
T*[1, 2, 12, 110, 1340, 20284, 366660,  7710392, 185218134, ...]
= [1, 3, 20, 195, 2476, 38605, 712984, 15223599, 369356822, ...];
T*[1, 3, 20, 195, 2476, 38605,  712984, 15223599, 369356822, ...]
= [1, 4, 30, 315, 4214, 68308, 1299696, 28396003, 701068918, ...]; ...
RELATED TRIANGLE.
Compare this triangle to the triangle A088956(n,k) = (n-k+1)^(n-k-1)*C(n,k), that transforms diagonals in the table of coefficients in the iterations of x/(1-x):
1;
1, 1;
3, 2, 1;
16, 9, 3, 1;
125, 64, 18, 4, 1;
1296, 625, 160, 30, 5, 1;
16807, 7776, 1875, 320, 45, 6, 1; ...
		

Crossrefs

Cf. variants: A233531, A088956.

Programs

  • PARI
    /* From Root Series G, Calculate T(n,k) of Triangle: */
    {T(n, k) = my(F=x, M, N, P, m=max(n, k)); M=matrix(m+2, m+2, r, c, F=x;
    for(i=1, r+c-2, F=subst(F, x, G +x*O(x^(m+2)))); polcoeff(F, c));
    N=matrix(m+1, m+1, r, c, M[r, c]);
    P=matrix(m+1, m+1, r, c, M[r+1, c]); (P~*N~^-1)[n+1, k+1]}
    /* Calculates Root Series G and then Prints ROWS of Triangle: */
    {ROWS=12;V=[1,1];print("");print1("Root Sequence: [1, 1, ");
    for(i=2,ROWS,V=concat(V,0);G=x*truncate(Ser(V));
    for(n=0,#V-1,if(n==#V-1,V[#V]=n^n-T(n,0));for(k=0,n, T(n,k)));print1(V[#V]", "););
    print1("...]");print("");print("");print("Triangle begins:");
    for(n=0,#V-2,for(k=0,n,print1(T(n,k),", "));print(""))}
Showing 1-1 of 1 results.