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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 (list; graph; refs; listen; history; text; internal format)
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 (* Jean-François 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 Jean-François Alcover, Feb 22 2020

STATUS

approved

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Last modified January 24 16:44 EST 2021. Contains 340411 sequences. (Running on oeis4.)