OFFSET
2,3
COMMENTS
EXAMPLE
a(4) = 3 because 4!! = 8 and 8 -/+ 3 = 5 and 11 are primes with smallest equal distances from 4!!
MATHEMATICA
smbp[n_]:=Module[{m=0, n2=n!!}, While[Total[Boole[PrimeQ[n2+{m, -m}]]] != 2, m++]; m]; Array[smbp, 60, 2] (* Harvey P. Dale, Sep 02 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Sep 18 2002
EXTENSIONS
More terms from David Wasserman, Jan 17 2005
STATUS
approved