a(n) = 21*2^n-1.
20, 41, 83, 167, 335, 671, 1343, 2687, 5375, 10751, 21503, 43007, 86015, 172031
2 seqfan posts
Fri Oct 21 21:18:09 CEST 2011 [seqfan] Re: Problem with A086224 cross refs
Fri Oct 21 21:03:15 CEST 2011 [seqfan] Problem with A086224 cross refs
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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