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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.

A247237 Triangle read by rows: T(n,k) is the coefficient in the transformation Sum_{k=0..n} (k+1)*x^k = Sum_{k=0..n} T(n,k)*(x-k)^k.

Original entry on oeis.org

1, 3, 2, 3, 14, 3, 3, 50, 39, 4, 3, 130, 279, 84, 5, 3, 280, 1479, 984, 155, 6, 3, 532, 6519, 8544, 2675, 258, 7, 3, 924, 25335, 61464, 34035, 6138, 399, 8, 3, 1500, 89847, 388056, 356595, 106938, 12495, 584, 9, 3, 2310, 297207, 2225136, 3259635, 1524438, 284655, 23264, 819, 10
Offset: 0

Views

Author

Derek Orr, Nov 27 2014

Keywords

Comments

Consider the transformation 1 + 2x + 3x^2 + 4x^3 + ... + (n+1)*x^n = T(n,0)*(x-0)^0 + T(n,1)*(x-1)^1 + T(n,2)*(x-2)^2 + ... + T(n,n)*(x-n)^n, for n >= 0.

Examples

			From _Wolfdieter Lang_, Jan 14 2015: (Start)
The triangle T(n,k) starts:
n\k 0    1      2       3       4       5      6     7   8  9 ...
0:  1
1:  3    2
2:  3   14      3
3:  3   50     39       4
4:  3  130    279      84       5
5:  3  280   1479     984     155       6
6:  3  532   6519    8544    2675     258      7
7:  3  924  25335   61464   34035    6138    399     8
8:  3 1500  89847  388056  356595  106938  12495   584   9
9:  3 2310 297207 2225136 3259635 1524438 284655 23264 819 10
...
-----------------------------------------------------------------
n = 3: 1 + 2*x + 3*x^2 + 4*x^3 = 3*(x-0)^0 +  50*(x-1)^1 + 39*(x-2)^2 + 4*(x-3)^3.
(End)
		

Crossrefs

Programs

  • PARI
    T(n,k)=(k+1)-sum(i=k+1,n,(-i)^(i-k)*binomial(i,k)*T(n,i))
    for(n=0,10,for(k=0,n,print1(T(n,k),", ")))

Formula

T(n,n) = n+1, n >= 0.
T(n,1) = n(n+1)(n+2)(3*n+1)/12 (A153978), for n >= 1.
T(n,n-1) = n^3 + n^2 + n (A027444), for n >= 1.
T(n,n-2) = (n-1)^2 (n^3-2)/2, for n >= 2.

Extensions

Edited by Wolfdieter Lang, Jan 14 2015