OFFSET
1,2
COMMENTS
Does every generation after the initial 1 contain a prime?
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
Gevorg Hmayakyan, Trig identity for a(n)
FORMULA
Product_{j=0..n-1} cos(4^j) = 2^(-n+1)*Sum_{i=2^(n-1)..2^n-1} cos(a(i)). - Gevorg Hmayakyan, Jan 15 2017
Sum_{i=2^(n-1)..2^n-1} cos(a(i)/4^(n-1)*Pi/2) = 0. - Gevorg Hmayakyan, Jan 15 2017
a(n) = 2*A032925(n-1) + 1 for n>=2. - Alois P. Heinz, Jan 29 2023
EXAMPLE
0th generation: 1
1st generation: 3 5
2nd generation: 11 13 19 21
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Dec 07 2008
STATUS
approved