A215523 Slowest increasing sequence of alternate-parity integers m such that 2m+1 is prime.

1, 2, 3, 6, 9, 14, 15, 18, 21, 26, 29, 30, 33, 36, 39, 44, 51, 54, 63, 68, 69, 74, 75, 78, 81, 86, 89, 90, 95, 96, 99, 114, 119, 120, 125, 128, 131, 134, 135, 138, 141, 146, 153, 156, 165, 168, 173, 174, 179, 186, 189, 194, 209, 210, 215, 216, 219, 224, 231

Offset

1,2

Comments

Corresponding primes: 3,5,7,13,19,29,31,37,43,53,59,61,67,73, ...

Links

Zak Seidov, Table of n, a(n) for n = 1..1000

Mathematica

s={1}; a=2; Do[While[!PrimeQ[ 2a+1], a=a+2]; AppendTo[s, a]; a++, {999}]; s

Crossrefs

Sequence in context: A280422 A309897 A128955 * A306247 A348865 A244739

Adjacent sequences: A215520 A215521 A215522 * A215524 A215525 A215526

Keyword

nonn

Author

Zak Seidov, Aug 14 2012

Status

approved