31641

Appears in sequences

• Numbers k such that phi(sigma(k)+k) = sigma(k).at n=20A068366
• a(n) = (n-1)*(n-2)^3 - A003878(n-3), with a(1) = a(2) = 0 and a(3) = 2.at n=37A075681
• Integers k such that nextprime(k^5) - prevprime(k^5) = 4.at n=28A090123
• a(n) = (n!/(n+1))*Sum_{k=0..n} binomial(n+k-1,k)/k!.at n=7A111140
• Expansion of Product_{k >= 0} (1 + A147954(k)*x^k).at n=34A147955
• Ulam numbers k such that k/3 is also an Ulam number.at n=42A287212
• E.g.f. satisfies A(x) = exp(x + x^3/3 * A(x)^3).at n=7A362478
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * Sum_{j=0..floor(n/3)} (k/6)^j * (3*j+1)^(n-2*j-1) / (j! * (n-3*j)!).at n=52A362490
• Centered pentagonal numbers which are products of three distinct primes.at n=17A364610