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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.

A059781 Triangle T(n,k) giving exponent of power of 2 dividing entry (n,k) of trinomial triangle A027907.

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 1, 4, 0, 4, 1, 2, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 2, 0, 0, 1, 0, 0, 0, 1, 0, 0, 2, 0, 0, 0, 3, 2, 4, 1, 3, 4, 3, 0, 3, 4, 3, 1, 4, 2, 3, 0, 0, 0, 0, 2, 1, 1, 1, 8, 0, 0, 0, 8, 1, 1, 1, 2, 0, 0, 0, 0, 1, 0, 1, 0
Offset: 0

Views

Author

N. J. A. Sloane, Feb 22 2001

Keywords

Examples

			0; 0,0,0; 0,1,0,1,0; ...
		

References

  • Boris A. Bondarenko, Generalized Pascal Triangles and Pyramids (in Russian), FAN, Tashkent, 1990, ISBN 5-648-00738-8.

Programs

  • Maple
    with(numtheory): T := proc(i,j) option remember: if i >= 0 and j=0 then RETURN(1) fi: if i >= 0 and j=2*i then RETURN(1) fi: if i >= 1 and j=1 then RETURN(i) fi: if i >= 1 and j=2*i-1 then RETURN(i) fi: T(i-1,j-2)+T(i-1,j-1)+T(i-1,j): end: for i from 0 to 20 do for j from 0 to 2*i do if T(i,j) mod 2 = 1 then printf(`%d,`,0) else printf(`%d,`, ifactors(T(i,j))[2,1,2] ) fi: od:od: # James Sellers, Feb 22 2001

Extensions

More terms from James Sellers, Feb 22 2001