5855409domain: NAppears in sequencesG.f. is the polynomial (1-x^3) * (1-x^6) * (1-x^9) * (1-x^12) * (1-x^15) * (1-x^18) * (1-x^21) * (1-x^24) * (1-x^27) / (1-x)^9.at n=25A162602Number of 0..n arrays x(0..5) of 6 elements with each no smaller than the sum of its two previous neighbors modulo (n+1).at n=21A207103