

A178937


Partial sums of number of different shapes formed by bending a piece of wire of length n in the plane A066372.


0



1, 2, 4, 7, 12, 20, 35, 58, 101, 172, 300, 509, 888, 1538, 2683, 4611, 8033, 13941, 24236, 41766, 72504, 125592, 217563, 374757, 648378, 1120243, 1934800, 3328622, 5743517, 9901009, 17061027, 29314809, 50478219, 86859244, 149408560, 256438542, 440869300
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OFFSET

1,2


COMMENTS

Number of different shapes formed by bending (+ or  90 degrees at each bend) a piece of wire of length <= n in the plane.


LINKS

Table of n, a(n) for n=1..37.


EXAMPLE

a(9) = 1 + 1 + 2 + 3 + 5 + 8 + 15 + 23 + 43 = 101 is prime. The next prime is a(15) = 2683.


MATHEMATICA

Cases[Import["https://oeis.org/A066372/b066372.txt", "Table"], {_, _}][[All, 2]] // Accumulate (* JeanFrançois Alcover, Feb 22 2020 *)


CROSSREFS

Cf. A001997, A066372.
Sequence in context: A186537 A079970 A079816 * A168368 A305106 A182746
Adjacent sequences: A178934 A178935 A178936 * A178938 A178939 A178940


KEYWORD

nonn,walk


AUTHOR

Jonathan Vos Post, Dec 30 2010


EXTENSIONS

More terms from Nathaniel Johnston, Jan 04 2011
More terms from A066372 by JeanFrançois Alcover, Feb 22 2020


STATUS

approved



