OFFSET
0,5
COMMENTS
It appears that a(n+2) is successively either one 1 or a string of the odd numbers.
Conjecture: the rank of 1's is A005097(n+1). This is another link between Bernoulli numbers and primes via A190339(n).
Apparently (essentially) a duplicate of A049653. - R. J. Mathar, Mar 30 2014
EXAMPLE
a(0)=2-2=0, a(1)=4-3=1, a(2)=6-5=1, a(3)=8-7=1, a(4)=10-7=3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul Curtz, Mar 04 2014
STATUS
approved