10141965domain: NAppears in sequencesa(1)=a(2)=1; thereafter, a(n+1) = a(n) + a(n-1) + 1 if n is a multiple of 5, otherwise a(n+1) = a(n) + a(n-1).at n=34A124502a(n) = Sum_{i=0..n} Fibonacci(5*i).at n=7A138134