A072275 - OEIS

A072275

Least m such that one less than m-th prime has n divisors (or 0 if no such prime exists).

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

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OFFSET

2,1

LINKS

Table of n, a(n) for n=2..55.

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: A273014 A336321 A359446 * A122989 A222246 A353828

Adjacent sequences: A072272 A072273 A072274 * A072276 A072277 A072278

KEYWORD