28721

Appears in sequences

• Numbers k such that sopf(k)*nud(k) = pi(k), where sopf(k)=A008472, nud(k)=A034444 and pi(k)=A000720.at n=10A064015
• (prime(n)*(prime(n+1)-1) + (prime(n)-1)*prime(n+1)) / 2.at n=37A099909
• Expansion of x*(2-4*x^2-x^3)/((1-x)^2*(1-x-x^2)).at n=21A133931
• Minimum power to which 2 must be raised so that the first n digits of the result are the digits of A155699(n).at n=3A155700
• Number of n X 2 0..3 arrays with no element equal to zero plus the sum of elements to its left or zero plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.at n=45A239852
• Integers k such that k^2 can be written as the sum of three positive fourth powers.at n=8A365657
• Primitive solutions k to k^2 = u^4 + v^4 + w^4, with u, v, w > 0.at n=2A365688