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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.

A319862 Triangle read by rows, 0 <= k <= n: T(n,k) is the denominator of the k-th Bernstein basis polynomial of degree n evaluated at the interval midpoint t = 1/2; numerator is A319861.

Original entry on oeis.org

1, 2, 2, 4, 2, 4, 8, 8, 8, 8, 16, 4, 8, 4, 16, 32, 32, 16, 16, 32, 32, 64, 32, 64, 16, 64, 32, 64, 128, 128, 128, 128, 128, 128, 128, 128, 256, 32, 64, 32, 128, 32, 64, 32, 256, 512, 512, 128, 128, 256, 256, 128, 128, 512, 512, 1024, 512, 1024, 128, 512, 256, 512, 128, 1024, 512, 1024
Offset: 0

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Keywords

Examples

			Triangle begins:
    1;
    2,   2;
    4,   2,   4;
    8,   8,   8,   8;
   16,   4,   8,   4,  16;
   32,  32,  16,  16,  32,  32;
   64,  32,  64,  16,  64,  32,  64;
  128, 128, 128, 128, 128, 128, 128, 128;
  256,  32,  64,  32, 128,  32,  64,  32, 256;
  512, 512, 128, 128, 256, 256, 128, 128, 512, 512;
  ...
		

Crossrefs

Programs

  • GAP
    Flat(List([0..11],n->List([0..n],k->2^n/Gcd(Binomial(n,k),2^n)))); # Muniru A Asiru, Sep 30 2018
    
  • Maple
    a:=(n,k)->2^n/gcd(binomial(n,k),2^n): seq(seq(a(n,k),k=0..n),n=0..11); # Muniru A Asiru, Sep 30 2018
  • Mathematica
    T[n_, k_] = 2^n/GCD[Binomial[n, k], 2^n];
    tabl[nn_] = TableForm[Table[T[n, k], {n, 0, nn}, {k, 0, n}]];
  • Maxima
    T(n, k) := 2^n/gcd(binomial(n, k), 2^n)$
    tabl(nn) := for n:0 thru nn do print(makelist(T(n, k), k, 0, n))$
    
  • Sage
    def A319862(n,k): return denominator(binomial(n,k)/2^n)
    flatten([[A319862(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Jul 20 2021

Formula

T(n, k) = denominator of binomial(n,k)/2^n.
T(n, k) = 2^n/A082907(n,k).
A319862(n, k)/T(n, k) = binomial(n,k)/2^n.
T(n, n-k) = T(n, k).
T(n, 0) = 2^n.
T(n, 1) = A075101(n).