A108283 -id:A108283 - cp's OEIS frontend

A108284 Triangle read by rows, related to A108283.

1, 3, 2, 6, 11, 6, 10, 39, 54, 24, 15, 114, 304, 324, 120, 21, 300, 1384, 2664, 2280, 720, 28, 741, 5598, 17364, 25800, 18360, 5040, 36, 1757, 21054, 99012, 227400, 273720, 166320, 40320, 45, 4052, 75504, 518592, 1728816, 3131400, 3160080, 1673280, 362880, 55, 9162, 262104, 2564892, 11934816, 30523800, 45496080, 39473280, 18506880, 3628800

Offset: 1

Gary W. Adamson, May 30 2005

			Triangle begins:
1;
3, 2;
6, 11, 6;
10, 39, 54, 24;
15, 114, 304, 324, 120; ...
Row 2: (3, 2, 0, 0, 0...), is the inverse binomial transform of column 2 of A108283: (3, 5, 7, 9...).

Cf. A108283.

(* T = A108283 *) T[, 1] := 1; T[n, n_] := n*(n + 1)/2; T[n_, k_] := (1 - (n - k + 1)^k*(k^2 - k*n + 1))/(n - k)^2; row[n_] := (TT = Table[T[k, n], {k, n, 2*n - 1}]; Table[Differences[TT, k], {k, 0, n - 1}][[All, 1]]); Table[row[n], {n, 1, 10}] // Flatten (* Jean-François Alcover, Sep 13 2016 *)

n-th row is the inverse binomial transform of n-th column of A108283.

More terms from Jean-François Alcover, Sep 13 2016

A108285 Triangle read by rows, generated from (1, 2, 3, ...).

Original entry on oeis.org

1, 1, 3, 1, 4, 6, 1, 5, 11, 10, 1, 6, 18, 26, 15, 1, 7, 27, 58, 57, 21, 1, 8, 38, 112, 179, 120, 28, 1, 9, 51, 194, 453, 543, 247, 36

Offset: 0

Gary W. Adamson, May 30 2005

By diagonals (d=1,2,3,...) going to the left with (1,3,6,...) = d(1), these are sequences of the form (k-th term a(k) = d*a(k-1) + k). Example: 1, 7, 38, 194, ... (the 5th diagonal) = A014827, is generated by a(k) = 5*a(k-1) + k. Diagonal 2 = (1, 4, 11, 26, ...) = A000295; Diagonal 3 = (1, 5, 18, ...) = A000340; Diagonal 4 = (1, 6, 27, ...) = A014825.

Triangle A108243 is generated by analogous operations from (..., 3, 2, 1) instead of (1, 2, 3, ...).

			4th column (offset) = 10, 26, 58, 112, ...= f(x), x = 1, 2, 3; x^3 + 2x^2 + 3x + 4.
First few rows of the triangle are:
  1;
  1, 3;
  1, 4, 6;
  1, 5, 11, 10;
  1, 6, 18, 26, 15;
  1, 7, 27, 58, 57, 21;
  1, 8, 38, 112, 179, 120, 28;
  ...

Cf. A108286, A000295, A000349, A014825, A000217, A108283, A108284, A108286.

n-th column = f(x), x = 1, 2, 3, ...; x^(n) + 2*x^(n-1) + 3*x^(n-2) + ... + (n+1).

cp's OEIS Frontend

A108284 Triangle read by rows, related to A108283.

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