2750067domain: NAppears in sequencesTriangle, read by rows, where row n equals the coefficients of y^k in R_{n-1}(y+y^2) for k=3..n, where R_n(y) is the n-th row polynomial in y for n>=3 with R_3(y)=y^3.at n=42A187120A diagonal of triangle A187120.at n=6A187122