27118domain: NAppears in sequencesa(n) = C(n+6, 6) - n - 1.at n=13A062989Numbers k such that k^4 + 1, (k+2)^4 + 1 and (k+4)^4 + 1 are all primes.at n=22A073476Convolution of the even-indexed triangular numbers (A014105) and the squares (A000290).at n=13A277228Numbers k such that 10^k - 800001 is prime.at n=20A288822