28838

Appears in sequences

• All 81 combinations of prefixing and following a(n) by a single digit are nonprime.at n=15A032734
• Composite numbers k such that all the decimal concatenations ik and ikj (i, j = 1...9) are also composite.at n=9A032737
• Triangle T(n,k) = ((-1)^(n+k)/(n+1))*Sum_{j=0..n} (-1)^j*j!*Stirling2(n, j)* binomial(n-j, k)*binomial(n+j, j), read by rows.at n=18A156653
• Number of partitions of n having no parts with multiplicity 4.at n=40A184639
• Expansion of 1/(1 - Sum_{k>=1} k*x^(2*k)/(1 - x^k)).at n=19A321262
• Triangle of coefficients of quasi-Stirling polynomials.at n=18A331998