A236628 - OEIS

%I #14 Apr 28 2016 11:32:23

%S 2,2,4,2,6,4,12,2,6,4,14,4,6,4,26

%N Triangle read by rows in which T(n,k) is the number of parts in the k-th region of the set of overcompositions of n, with overcompositions in colexicographic order.

%C Right border gives A236002, n >= 1.

%C Row sums give A236625, n >= 1.

%e Written as an irregular triangle in which row n has length 2^n the sequence begins:

%e 2;

%e 2, 4;

%e 2, 6, 4, 12;

%e 2, 6, 4, 14, 4, 6, 4, 26;

%e ...

%e For n = 3 the diagram shows the four regions of the overcompositions of 3, with overcompositions in colexicographic order.

%e ------------------------------------------------

%e .  Diagram of            Regions of the diagram

%e overcompositions        ------------------------

%e .    of 3                k: 1     2   3       4

%e ------------------------------------------------

%e .    _ _ _                  _     _           _

%e 1   |.| | |                |.|   | |         | |

%e 2   |_| | |                |_|  _| |         | |

%e 3   |  .|.|                    |  .|         |.|

%e 4   |   |.|                    |   |         |.|

%e 5   |  .| |                    |  .|         | |

%e 6   |_ _| |                    |_ _|  _     _| |

%e 7   |.|  .|                          |.|   |  .|

%e 8   | |  .|                          | |   |  .|

%e 9   |.|   |                          |.|   |   |

%e 10  |_|   |                          |_|  _|   |

%e 11  |    .|                              |    .|

%e 12  |_ _ _|                              |_ _ _|

%e ...

%e Number of parts.........:   2     6   4      12

%e .

%e Every row of every region contains only one part.

%Y Cf. A236002, A236625, A236626.

%K nonn,tabf,more

%O 1,1

%A _Omar E. Pol_, Feb 01 2014