a(2n) = -(2^(2n+1) + 1), a(2n+1) = (2^(n+1) - (-1)^n)^2.
3, 1, 9, 25, 33, 49, 129, 289, 513, 961, 2049, 4225, 8193, 16129, 32769
2 seqfan posts
Sat Dec 12 12:45:59 CET 2009 [seqfan] Re: Divisibility sequences in OEIS.
Thu Nov 19 17:19:12 CET 2009 [seqfan] detective work related to Creighton Dement's "Floretions"
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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