This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A103799 Indices n such that A019565(n)+2 is prime. 2
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS 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: A057910 A120351 A022305 * A175817 A256773 A141104 Adjacent sequences:  A103796 A103797 A103798 * A103800 A103801 A103802 KEYWORD easy,nonn AUTHOR Lei Zhou, Feb 22 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 10 14:27 EST 2019. Contains 329896 sequences. (Running on oeis4.)