339150

Appears in sequences

• Numbers n such that n = concatenate(a, b) and sigma(a) + sigma(b) = phi(n).at n=18A249065
• a(n) = n*(n+1)*(n+2)*(n+3)*(2*n+1)/12.at n=17A356251
• Triangle read by rows: T(n, k) = binomial(n, k)*binomial(2*n+k, k), 0 <= k <= n.at n=40A370258