54051

Appears in sequences

• Indices of terms in A091074 which are prime numbers.at n=45A091076
• Numbers n such that 4*10^n + 5*R_n - 2 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=20A102991
• Triangle T(n, k) = (f(k, n-k+1) + f(n-k+1, k))/2 where f(n, k) = (1/2)*Sum_{j=1..2*n} k^j, read by rows.at n=23A173567
• Triangle T(n, k) = (f(k, n-k+1) + f(n-k+1, k))/2 where f(n, k) = (1/2)*Sum_{j=1..2*n} k^j, read by rows.at n=25A173567
• Sum of the prime parts in the partitions of n into 10 parts.at n=39A309471
• Irregular triangle read by rows: row n consists of the coefficients in the expansion of the polynomial (1/(2*w)) * (x^2 + x) * ((((v + w)/2)^(n - 1)) * (x^2 + 2*x + 4 + w) - (((v - w)/2)^(n - 1)) * (x^2 + 2*x + 4 - w)), where v = x^2 + 4*x + 4 and w = sqrt(x^4 + 4*x^3 + 12*x^2 + 20*x + 12).at n=51A386874