A084361 a(1) = 1; a(n+1) is the least prime of the form (2^k)*a(n)+-1, for some positive k.

1, 3, 5, 11, 23, 47, 751, 6007, 24029, 192233, 768931, 98423167, 206408341520383, 54108708279519281153, 907793486286483356068610047, 58098783122334934788391043009

Offset

1,2

Links

Table of n, a(n) for n=1..16.

Example

a(7) = 751 because a(6)=47 and in 2*47-1, 2*47+1, 4*47-1, 4*47+1, ... 16*47-1, ...: 751 is the first prime.

Crossrefs

Cf. A083201.

Sequence in context: A335883 A030494 A246491 * A077229 A335098 A018113

Adjacent sequences: A084358 A084359 A084360 * A084362 A084363 A084364

Keyword

nonn

Author

Don Reble, Jun 21 2003

Status

approved