OFFSET
0,3
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..25
Peter Kagey and William Keehn, Counting Tilings of the n X m Grid, Cylinder, and Torus, J. Int. Seq. (2024) Vol. 27, Art. No. 24.6.1. See p. 2.
FORMULA
a(n) = (n^(n^2) + 2*n^((n^2 + 3*(n mod 2))/4) + n^((n^2 + (n mod 2))/2))/4.
MAPLE
a:= n-> (n^(n^2)+2*n^((n^2+3*(n mod 2))/4)+n^((n^2+(n mod 2))/2))/4:
seq(a(n), n=0..10); # Alois P. Heinz, May 12 2021
PROG
(PARI) a(n) = {(n^(n^2) + 2*n^((n^2 + 3*(n%2))/4) + n^((n^2 + (n%2))/2))/4}
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Apr 14 2021
STATUS
approved