25971865920domain: NAppears in sequencesa(n) = denominator of Sum_{k=1..n} 1/k^2.at n=12A007407a(n) = denominator of Sum_{k=1..n} 1/k^2.at n=13A007407Denominators of row sums of rational triangle A120072/A120073.at n=11A120077Denominators of row sums of rational triangle A120072/A120073.at n=12A120077