OFFSET
1,1
COMMENTS
Is this (apart from 2) the subset of primes in A134026? - R. J. Mathar, Sep 17 2012
LINKS
Christian Salas, Cantor Primes as Prime-Valued Cyclotomic Polynomials, arXiv preprint arXiv:1203.3969, 2012.
MAPLE
isA216731 := proc(n)
if isprime(n) then
floor(log[3](2*n)) = floor(log[3](3*n)) ;
else
false;
end if;
end proc:
for n from 2 to 250 do
p := ithprime(n) ;
if isA216731(p) then
printf("%d, ", p) ;
end if;
end do: # R. J. Mathar, Sep 17 2012
MATHEMATICA
isA216731[n_] := If[PrimeQ[n], Floor[Log[3, 2*n]] == Floor[Log[3, 3*n]], False]; Reap[For[n = 2, n <= 100, n++, p = Prime[n]; If[isA216731[p], Print[p]; Sow[p]]]][[2, 1]] (* Jean-François Alcover, Mar 06 2014, after R. J. Mathar *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 17 2012
STATUS
approved