OFFSET
1,1
LINKS
Pierre CAMI, Table of n, a(n) for n = 1..325
EXAMPLE
3*2^1-1-2=3 3*2^1-1=5 3*2^1-1+2=7 so a(1)=3.
3*2^4-1=47 3*2^4-1+6=53 3*2^4-1+12=59 so a(4)=3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Oct 26 2013
STATUS
approved