The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A236569 Least term p of A236568 with 2*n - p prime, or 0 if such a prime p does not exist. 2
 0, 0, 3, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 11, 3, 3, 5, 31, 3, 5, 3, 3, 5, 3, 5, 11, 3, 5, 31, 3, 3, 5, 31, 3, 5, 3, 3, 5, 43, 3, 5, 3, 5, 11, 3, 5, 43, 31, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 11, 43, 11, 43, 31, 3, 5, 3, 5, 11, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS The conjecture in A236566 implies that a(n) > 0 for all n > 2. LINKS Zhi-Wei Sun, Table of n, a(n) for n = 1..10000 EXAMPLE a(3) = 3 since prime(3 + 2) + 2 = 11 + 2 = 13 and 2*3 - 3 = 3 are both prime, but prime(2 + 2) + 2 = 9 is not. MATHEMATICA p[m_]:=PrimeQ[Prime[m+2]+2] Do[Do[If[p[Prime[k]]&&PrimeQ[2n-Prime[k]], Print[n, " ", Prime[k]]; Goto[aa]], {k, 1, PrimePi[2n-1]}]; Print[n, " ", 0]; Label[aa]; Continue, {n, 1, 100}] CROSSREFS Cf. A000040, A020481, A236566, A236568. Sequence in context: A302387 A049613 A002373 * A103153 A162022 A318240 Adjacent sequences: A236566 A236567 A236568 * A236570 A236571 A236572 KEYWORD nonn AUTHOR Zhi-Wei Sun, Jan 29 2014 STATUS approved

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

Last modified August 13 20:02 EDT 2024. Contains 375144 sequences. (Running on oeis4.)