A336491 Consider the figure made up of a row of n adjacent congruent rectangles, with diagonals of all possible rectangles drawn; a(n) = number of interior vertices where exactly five lines cross.

0, 0, 0, 1, 2, 2, 2, 12, 26, 20, 10, 38, 74, 118, 102, 114, 126, 178, 238, 306, 382, 466, 558, 762, 774, 778, 774, 942, 1126, 1326, 1542, 1910, 2310, 2742, 2762, 3070, 3394, 3734, 4090, 4294, 4498, 4966, 5458, 6434, 6910, 7402, 7910, 8834, 9806, 10410, 11030

Offset

1,5

Links

Lars Blomberg, Table of n, a(n) for n = 1..500

Crossrefs

Cf. A334701, A336489, A336490.

Sequence in context: A106541 A077945 A077991 * A049148 A369077 A183584

Adjacent sequences: A336488 A336489 A336490 * A336492 A336493 A336494

Keyword

nonn

Author

Lars Blomberg, Jul 25 2020

Status

approved