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.

A112360 Triangle read by rows: T(n,k) is the LCM of all C(n,k) integers from 1 + C(n,0) + C(n,1) + ... + C(n,k-1) to C(n,0) + C(n,1) + ... + C(n,k) (0 <= k <= n).

Original entry on oeis.org

1, 1, 2, 1, 6, 4, 1, 12, 210, 8, 1, 60, 27720, 5460, 16, 1, 60, 720720, 13385572200, 3398220, 32, 1, 420, 232792560, 219060189739591200, 60218289392461200, 4076731260, 64, 1, 840, 2329089562800, 1182266884102822267511361600
Offset: 0

Views

Author

Amarnath Murthy, Sep 07 2005

Keywords

Comments

Column 1 yields A003418. a(n,n) = 2^n. - Emeric Deutsch, Feb 03 2006

Examples

			Triangle begins:
  1;
  1,  2;
  1,  6,     4;
  1, 12,   210,    8;
  1, 60, 27720, 5460, 16;
  ...
The row for n = 3 is
1....3..........3.......1
1 lcm(2*3*4) lcm(5*6*7) 8 ====> 1 12 210 8.
		

Crossrefs

Programs

  • Maple
    T:=proc(n,k) if n=0 and k=0 then 1 else lcm(seq(j,j=1+sum(binomial(n,i),i=0..k-1)..sum(binomial(n,i),i=0..k))) fi end: for n from 0 to 7 do seq(T(n,k),k=0..n) od; # yields sequence in triangular form - Emeric Deutsch, Feb 03 2006

Extensions

More terms from Emeric Deutsch, Feb 03 2006