OFFSET
1,1
COMMENTS
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..26
EXAMPLE
3 = 2*2^2 - 5; 19 = 3*2^3 - 5; 59 = 4*2^4 - 5.
MAPLE
#choose N large, then S is the desired set
f:=n->n*2^n - 5:
S:={}:
for n from 0 to N do if(isprime(f(n))) then S:=S union {f(n)}: fi: od
MATHEMATICA
Select[Table[n*2^n-5, {n, 2, 100}], PrimeQ] (* Harvey P. Dale, Aug 06 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Patrick Devlin, Apr 25 2012
STATUS
approved