

A233970


Toothpick sequence on hexagonal net starting from the vertex of a 60degree wedge (see Comments lines for precise definition).


6



0, 1, 3, 5, 9, 11, 15, 21, 29, 31, 35, 41, 51, 61, 69, 83, 99, 101, 105, 111, 121, 131, 141, 159, 183, 205, 213, 227, 249, 275, 291, 321, 353, 355, 359, 365, 375, 385, 395, 413, 437, 459, 469, 487, 515, 553, 581, 627, 683, 737, 745, 759, 781, 807
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OFFSET

0,3


COMMENTS

Toothpicks are connected by their endpoints. The toothpicks placed in north direction are prohibited. The sequence gives the number of toothpicks after nth stage in the structure. A233971 (the first differences) give the number of toothpicks added at nth stage.
First differs from A169780 at a(24).


LINKS



CROSSREFS

Cf. A139250, A161206, A161830, A169780, A182632, A182634, A182634, A182840, A233760, A233764, A233780, A233971, A233972.


KEYWORD

nonn


AUTHOR



STATUS

approved



