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.

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A214292 Triangle read by rows: T(n,k) = T(n-1,k-1) + T(n-1,k), 0 < k < n with T(n,0) = n and T(n,n) = -n.

Original entry on oeis.org

0, 1, -1, 2, 0, -2, 3, 2, -2, -3, 4, 5, 0, -5, -4, 5, 9, 5, -5, -9, -5, 6, 14, 14, 0, -14, -14, -6, 7, 20, 28, 14, -14, -28, -20, -7, 8, 27, 48, 42, 0, -42, -48, -27, -8, 9, 35, 75, 90, 42, -42, -90, -75, -35, -9, 10, 44, 110, 165, 132, 0, -132, -165, -110, -44, -10
Offset: 0

Views

Author

Reinhard Zumkeller, Jul 12 2012

Keywords

Examples

			The triangle begins:
    0:                              0
    1:                            1   -1
    2:                          2   0   -2
    3:                       3    2   -2   -3
    4:                     4    5   0   -5   -4
    5:                  5    9    5   -5   -9   -5
    6:                6   14   14   0  -14  -14   -6
    7:             7   20   28   14  -14  -28  -20   -7
    8:           8   27   48   42   0  -42  -48  -27   -8
    9:        9   35   75   90   42  -42  -90  -75  -35   -9
   10:     10   44  110  165  132   0 -132 -165 -110  -44  -10
   11:  11   54  154  275  297  132 -132 -297 -275 -154  -54  -11  .
		

Crossrefs

Programs

  • Haskell
    a214292 n k = a214292_tabl !! n !! k
    a214292_row n = a214292_tabl !! n
    a214292_tabl = map diff $ tail a007318_tabl
       where diff row = zipWith (-) (tail row) row
  • Mathematica
    row[n_] := Table[Binomial[n, k], {k, 0, n}] // Differences;
    T[n_, k_] := row[n + 1][[k + 1]];
    Table[T[n, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, Jul 31 2018 *)

Formula

T(n,k) = A007318(n+1,k+1) - A007318(n+1,k), 0<=k<=n, i.e. first differences of rows in Pascal's triangle;
T(n,k) = -T(n,k);
row sums and central terms equal 0, cf. A000004;
sum of positive elements of n-th row = A014495(n+1);
T(n,0) = n;
T(n,1) = A000096(n-2) for n > 1; T(n,1) = - A080956(n) for n > 0;
T(n,2) = A005586(n-4) for n > 3; T(n,2) = A129936(n-2);
T(n,3) = A005587(n-6) for n > 5;
T(n,4) = A005557(n-9) for n > 8;
T(n,5) = A064059(n-11) for n > 10;
T(n,6) = A064061(n-13) for n > 12;
T(n,7) = A124087(n) for n > 14;
T(n,8) = A124088(n) for n > 16;
T(2*n+1,n) = T(2*n+2,n) = A000108(n+1), Catalan numbers;
T(2*n+3,n) = A000245(n+2);
T(2*n+4,n) = A002057(n+1);
T(2*n+5,n) = A000344(n+3);
T(2*n+6,n) = A003517(n+3);
T(2*n+7,n) = A000588(n+4);
T(2*n+8,n) = A003518(n+4);
T(2*n+9,n) = A001392(n+5);
T(2*n+10,n) = A003519(n+5);
T(2*n+11,n) = A000589(n+6);
T(2*n+12,n) = A090749(n+6);
T(2*n+13,n) = A000590(n+7).

A163866 Partial sums of A007318.

Original entry on oeis.org

1, 2, 3, 4, 6, 7, 8, 11, 14, 15, 16, 20, 26, 30, 31, 32, 37, 47, 57, 62, 63, 64, 70, 85, 105, 120, 126, 127, 128, 135, 156, 191, 226, 247, 254, 255, 256, 264, 292, 348, 418, 474, 502, 510, 511, 512, 521, 557, 641, 767, 893, 977, 1013, 1022, 1023, 1024, 1034, 1079, 1199
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 06 2009

Keywords

Examples

			a(1)=0!/(0!(0-0)!)=1.
		

Crossrefs

Programs

  • Haskell
    a163866 n = a163866_list !! (n-1)
    a163866_list = scanl1 (+) $ concat a007318_tabl
    -- Reinhard Zumkeller, Jul 18 2015
    
  • Mathematica
    Flatten[Table[2^a-1+Sum[Binomial[a,p],{p,0,b}],{a,0,10},{b,0,a}]] (* Frank M Jackson, Apr 25 2011 *)
    Accumulate[Flatten[Table[Binomial[n,k],{n,0,11},{k,0,n}]]] (* Harvey P. Dale, Dec 04 2012 *)
  • PARI
    lista(nn) = {my(i=0, j=0, p=0); for (n=1, nn, p += binomial(i, j); print1(p, ", "); j++; if (j > i, j = 0; i++););} \\ Michel Marcus, Jan 25 2019

Formula

a(n) = Sum_{j=1..n-1} A007318(j).

Extensions

Entries checked by R. J. Mathar, Aug 11 2009
Showing 1-2 of 2 results.