45188

Appears in sequences

• Numbers k such that k^2 divides 21^k-1.at n=41A128401
• Number of 2 X 2 nonsingular 0..n matrices with a(1,1) <= a(1,2) <= a(2,1) <= a(2,2).at n=29A183763
• Numbers n such that n^9+9 and n^9-9 are prime.at n=36A239505
• Number of isoscent sequences of length n with maximal number of descents.at n=25A243484
• Triangle read by rows in which T(n,k) is the number of permutations avoiding 132 of length n with an independent set of size k in its coregraph.at n=52A262370
• G.f. A(x) satisfies A(x) = 1 + x*A(x)*(1 + x^4*A(x)^5).at n=15A365760