655974domain: NAppears in sequencesNumber of primes < 10^(2n) - sum of primes < 10^n.at n=5A139564Number of arrangements of 5 nonzero numbers x(i) in -n..n with the sum of div(x(i),x(i+1)), where div(a,b)=a/b produces the integer quotient implying a nonnegative remainder, equal to zero.at n=11A190074