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.

A098744 Triangle read by rows: row n gives the number of orbits of the group GA(n) acting on binary vectors of length 2^n and weight k, for n >= 0, 0 <= k <= 2^n.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 4, 5, 8, 9, 15, 16, 23, 24, 30, 30, 38, 30, 30, 24, 23, 16, 15, 9, 8, 5, 4, 2, 2, 1, 1, 1, 1
Offset: 0

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Author

Alexander Vardy (avardy(AT)ucsd.edu), Nov 15 2008

Keywords

Comments

GA(n) is the general affine group, the automorphism group of the Reed-Muller code RM(r,n).
Since the group is triply transitive, there's only one orbit for vectors of weight 0,1,2,3.

Examples

			Triangle begins:
1 1
1 1 1
1 1 1 1 1
1 1 1 1 2 1 1 1 1 (the 2 is because there are two orbits on vectors of length 8 and weight 4)
1 1 1 1 2 2 3 3 4 3 3 2 2 1 1 1 1
		

Crossrefs

Cf. A000214 (row sums). - Vladeta Jovovic, Feb 22 2009

Extensions

More terms from Vladeta Jovovic, Feb 22 2009