A144730 - OEIS

A144730

a(n) is the smallest positive integer m such that b * (Product_{k=1..n} a(k)) + 1 is prime, with b = 7.

4, 7, 13, 19, 33, 35, 36, 43, 48, 55, 59, 62, 87, 129, 149, 153, 159, 190, 228, 231, 245, 265, 266, 269, 284, 300, 329, 331, 340, 347, 372, 432, 449, 450, 461, 485, 496, 500, 514, 544, 560, 565, 594, 598, 605, 614, 639, 677, 684, 734, 736, 794, 804, 813, 882

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

MATHEMATICA

k = 7; a = {}; Do[If[PrimeQ[k n + 1], k = k n; AppendTo[a, n]], {n, 1, 3000}]; a (*Artur Jasinski*)

CROSSREFS

A046966, A046972, A144717, A144718, A144722, A144723, A144724, A144725, A144726, A144727, A144728, A144729, A144731

Sequence in context: A191868 A176003 A216880 * A058570 A134781 A127977

Adjacent sequences: A144727 A144728 A144729 * A144731 A144732 A144733

KEYWORD

nonn

AUTHOR

Artur Jasinski, Sep 19 2008

EXTENSIONS

Definition corrected by Georg Fischer, Jun 18 2021

STATUS

approved