A103799 Indices n such that A019565(n)+2 is prime.

0, 2, 4, 6, 10, 12, 14, 16, 22, 24, 26, 34, 36, 38, 44, 46, 50, 62, 64, 66, 70, 74, 78, 82, 84, 90, 92, 96, 104, 106, 116, 118, 124, 130, 132, 138, 142, 144, 150, 154, 162, 164, 170, 172, 176, 186, 190, 194, 224, 230, 242, 252, 258, 262, 264, 270, 274, 278, 302, 308

Offset

1,2

Links

Table of n, a(n) for n=1..60.

Example

A019565(0)=1, 1+2=3 is prime, so a(1)=0;
A019565(1)=2, 2+2=4 is not prime,
A019565(2)=3, 3+2=5 is prime, so a(2)=2;

Mathematica

A019565 = Function[tn, k1 = tn; o = 1; tt = 1; While[k1 > 0, k2 = Mod[k1, 2]; If[k2 == 1, tt = tt*Prime[o]]; k1 = (k1 - k2)/2; o = o + 1]; tt]; Do[cp = A019565[n] + 2; If[PrimeQ[cp], Print[n]], {n, 0, 1000}]

Crossrefs

Cf. A019565, A103796, A103797.

Sequence in context: A336066 A120351 A022305 * A175817 A256773 A141104

Adjacent sequences: A103796 A103797 A103798 * A103800 A103801 A103802

Keyword

easy,nonn

Author

Lei Zhou, Feb 22 2005

Status

approved