21441

Appears in sequences

• Expansion of 1/((1-x)(1-5x)(1-10x)).at n=4A016237
• a(n+1) = a(n) converted to base 9 from base 8 (written in base 10).at n=41A023391
• a(n) is the decimal concatenation of n and n^2.at n=20A053061
• Average of three successive primes squared, (prime(n)^2+prime(n+1)^2+prime(n+2)^2)/3, n>=3.at n=31A075893
• Given the infinite continued fraction i+(i/(i+(i/(i+...)))), where i is the square root of (-1), this is the numerator of the imaginary part of the convergents.at n=23A091808
• Triangle T(n, k, q) = Sum_{j=0..10} q^j * floor( binomial(n+1,k)*binomial(n-1,k-1)/(2^j*(n+1)) ) for q = 3, read by rows.at n=38A174045
• Triangle T(n, k, q) = Sum_{j=0..10} q^j * floor( binomial(n+1,k)*binomial(n-1,k-1)/(2^j*(n+1)) ) for q = 3, read by rows.at n=42A174045
• Constant term of the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.at n=16A192975
• a(n) = n*(5*n^2-8*n+5)/2.at n=21A226449
• Sum of the second largest parts of the partitions of n into 10 parts.at n=39A326597