20344613659domain: NAppears in sequencesChebyshev even-indexed U-polynomials evaluated at sqrt(7)/2.at n=15A030221Probable primes in A030221.at n=6A299109Expansion of (Product_{k>=1} (1 - x^k)^2/(1 - 5*x^k + x^(2*k)) - 1)/3.at n=15A387017