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A076604
a(1) = 11, a(n_even) = (a(n-1)^2-1)/2; a(n_odd) = a(n-1)+1.
4
11, 60, 61, 1860, 1861, 1731660, 1731661, 1499324909460, 1499324909461, 1123987592065117923655260, 1123987592065117923655261, 631674053558170970207436821512098200057586489060
OFFSET
1,1
COMMENTS
{11, 60, 61}, {61, 1860, 1861}, {1861, 1731660, 1731661}... are sides {a<b<c} of the right triangles, with hypotenuse c = b+1.
CROSSREFS
Sequence in context: A193230 A349120 A077036 * A076676 A044149 A044530
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Oct 21 2002
EXTENSIONS
a(12) from Lars Blomberg, Oct 08 2008
STATUS
approved