[seqfan] finite a(n) for q=0 and infinite a(n) for q>0?
юрий герасимов
2stepan at rambler.ru
Mon Oct 22 17:13:14 CEST 2018
Dear seqfans, if a(n) is the smallest k such that number of divisors m of k is
equal to n where m-q and m+q are both prime, then a(n) is finite sequence for q=0
and a(n) is infinite sequence for q>0? Example: a(n) = 2 for q=0; a(n) = 4, 18,
12, 192, 60, 240, 180, 2088, 3360, 4800, 1620, 6300, 7560, ... for q=1; a(n) = 5,
15, 165, 45, 225, 405, 315, 1575, 2205, 5985, 3465, 10395, ... for q=2, e.t.c.Thanjs.
JSG.
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