A116903 - OEIS

A116903

Seaweeds(n): number of n-step self-avoiding walks on upper two quadrants grid starting at origin.

1, 3, 7, 19, 49, 131, 339, 899, 2345, 6199, 16225, 42811, 112285, 296051, 777411, 2049025, 5384855, 14190509, 37313977, 98324565, 258654441, 681552747, 1793492411, 4725856129, 12439233695, 32778031159, 86295460555, 227399388019, 598784536563, 1577923781445, 4155176578581

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OFFSET

0,2

COMMENTS

These walks remind me of fluctuant seaweeds anchored to the sea bottom.

LINKS

Table of n, a(n) for n=0..30.

M. N. Barber et al., Some tests of scaling theory for a self-avoiding walk attached to a surface, 1978 J. Phys. A: Math. Gen. 11 1833. [Vladeta Jovovic, Nov 26 2008]

EXAMPLE

The 19 seaweeds of length 3. X marks the origin = anchor point.

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