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 A072275 Least m such that one less than m-th prime has n divisors (or 0 if no such prime exists). 0
 2, 3, 4, 7, 6, 0, 11, 12, 30, 0, 18, 0, 44, 79, 47, 0, 42, 0, 53, 106, 1581, 0, 82, 211, 1470, 595, 319, 0, 169, 0, 216, 2819, 177975, 38836904, 279, 0, 62947, 41203, 326, 0, 647, 0, 1795, 907, 8719625, 0, 369, 0, 841, 12545382, 6180, 0, 820, 190066763704011 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 LINKS MATHEMATICA Do[ If[ !PrimeQ[n], k = 1; While[ Length[ Divisors[ Prime[k] - 1]] != n, k++ ]; Print[k], Print[0]], {n, 6, 34}] CROSSREFS A000040(a(n)) = A066814(n). Sequence in context: A260426 A167151 A273014 * A122989 A222246 A321726 Adjacent sequences:  A072272 A072273 A072274 * A072276 A072277 A072278 KEYWORD nonn AUTHOR Lekraj Beedassy, Jul 09 2002 EXTENSIONS More terms from Robert G. Wilson v, Jul 15 2002 a(35) inserted and a(46)-a(55) added by Amiram Eldar, Feb 06 2019 STATUS approved

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Last modified October 21 20:44 EDT 2019. Contains 328315 sequences. (Running on oeis4.)