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.

A225725 Triangle of transformation semigroup sizes generated by a single element.

Original entry on oeis.org

1, 1, 3, 1, 10, 15, 2, 41, 129, 80, 6, 196, 1115, 1260, 510, 24, 20, 1057, 10395, 17780, 12840, 3744, 840, 6322, 105315, 258510, 264810, 135492, 47250, 4920, 0, 0, 504, 0, 420, 41393, 1160635, 4018000, 5318180, 3788400, 1837024, 513120, 38640, 0, 32256, 0, 26880, 0, 0, 2688
Offset: 0

Views

Author

Chad Brewbaker, May 14 2013

Keywords

Comments

If you take the powers of a finite function you generate a lollipop graph. A222029 organizes the lollipops by cycle size. The table organized by total lollipop size with the tail included is this triangle.

Examples

			T(1,1) = #{[0]} = 1.
T(2,1) = #{[0,1], [0,0], [1,1]} = 3.
T(2,2) = #{[1,0]} = 1.
Triangle begins:
:    1;
:    1;
:    3,      1;
:   10,     15,      2;
:   41,    129,     80,      6;
:  196,   1115,   1260,    510,     24,    20;
: 1057,  10395,  17780,  12840,   3744,   840;
: 6322, 105315, 258510, 264810, 135492, 47250, 4920, 0, 0, 504, 0, 420;
		

Crossrefs

First column is A000248.
Row sums are: A000312.
Row lengths are A000793.
Number of nonzero elements of rows give A009490.
Cf. A222029.

Programs

  • Ruby
    # See Brewbaker link.

Extensions

More terms, some terms corrected by Alois P. Heinz, Aug 17 2017