OFFSET
2,1
EXAMPLE
a(2) = 5 = (2 + 1/3) * (2 + 1/7),
a(3) = 11 = (2 + 1/3) * (2 + 1/5) * (2+1/7) = (2 + 1/3)^2 * (2 + 1/49),
a(7) = 277 = (2 + 1/3)^5 * ( 2 + 1/405) * (2 + 1/13630477).
PROG
(PARI) see link in A355626
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner and Markus Sigg, Jul 16 2022
STATUS
approved