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.

A127322 Second 4-dimensional hyper-tetrahedral coordinate; 4-D analog of A056557.

Original entry on oeis.org

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

Views

Author

Graeme McRae, Jan 10 2007

Keywords

Comments

If {(W,X,Y,Z)} are 4-tuples of nonnegative integers with W>=X>=Y>=Z ordered by W, X, Y and Z, then W=A127321(n), X=A127322(n), Y=A127323(n) and Z=A127324(n). These sequences are the four-dimensional analog of the three-dimensional A056556, A056557 and A056558.

Examples

			a(23)=2 because a(A000332(2+3)+A000292(2)) = a(A000332(2+3)+A000292(3)-1) = 2, so a(19) = a(24) = 2.
See A127321 for a table of A127321, A127322, A127323, A127324.
		

Crossrefs

Formula

For W>=X>=0, a(A000332(W+3)+A000292(X)) = a(A000332(W+3)+A000292(X+1)-1) = X A127322(n+1) = A127321(n)==A127324(n) ? 0 : A127322(n)==A127324(n) ? A127322(n)+1 : A127322(n)