OFFSET
0,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..25
FORMULA
a(n) = 1/8*(5^(n^2) + 2*5^(n^2/4) + 3*5^(n^2/2) + 2*5^((n^2+n)/2)) if n is even;
a(n) = 1/8*(5^(n^2) + 2*5^((n^2+3)/4) + 5^((n^2+1)/2) + 4*5^((n^2+n)/2)) if n is odd.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, May 15 2000
EXTENSIONS
Terms a(9) and beyond from Andrew Howroyd, Apr 15 2021
STATUS
approved