80401

Appears in sequences

• (Prime(prime(n))^2+1)/2.at n=21A092773
• Expansion of the o.g.f. (1 + 8*x + 10*x^2 + 8*x^3 + x^4)/((1 - x)^4*(1 + x)^2).at n=40A342362
• Irregular triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} with cycle descent number equal to k.at n=31A349106
• Centered square numbers which are sphenic numbers.at n=28A380882