A006773 Sum of squared spans of 2n-step polygons on square lattice.

0, 1, 5, 30, 186, 1164, 7344, 46732, 299604, 1932900, 12537542, 81705782, 534663812, 3511466838, 23136724382, 152888000934, 1012925595468, 6726766841438, 44767880394634, 298522284224824, 1994187071224056, 13343458013982572, 89420609914983270, 600088861692380354, 4032377457462571694, 27129080022839863318, 182726605700552001998

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• A. J. Guttmann and I. G. Enting, The size and number of rings on the square lattice, J. Phys. A 21 (1988), L165-L172.

Crossrefs

Cf. A006772.

Extensions

Name corrected, more terms from Andrey Zabolotskiy, Nov 09 2018