OFFSET
1,4
FORMULA
a(n) = (p(n)+n) modulo (p(n)-n) = (2*n) modulo (p(n)-n).
a(n) = 2*n for n > 11 because prime(n) > 3*n for n > 11.
MATHEMATICA
f[n_] := Block[{p = Prime[n]}, Mod[p + n, p - n]]; Array[f, 64] (* Robert G. Wilson v, May 27 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, May 27 2012
STATUS
approved