OFFSET
0,2
COMMENTS
Partial sums of denominators of successive convergents to continued fraction 1+2/(3+3/(4+4/(5+5/(6+6/(7+7/(8+8/(9+9/10+...))))))). The subsequence of primes in this partial sum begins: 19, 1273710986008283.
FORMULA
a(n) = SUM[i=0..n] A053519(i).
EXAMPLE
a(16) = 1 + 3 + 15 + 29 + 597 + 4701 + 4643 + 413691 + 4512993 + 17926611 + 695000919 + 9680369943 + 4380611853 + 2303928046437 + 39031251610227 + 25940523189513 + 1206420504316107 = 1273710986008283 is prime.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Mar 20 2010
STATUS
approved