43786

Appears in sequences

• Number of equilateral triangles formed out of matches that can be found in a hexagonal chunk of side length n in hexagonal array of matchsticks.at n=23A045949
• Semiprimes in A054552.at n=36A113690
• Let A(0) = 1, B(0) = 0 and C(0) = 0. Let B(n+1) = Sum_{k = 0..n} binomial(n,k)* A(k), C(n+1) = Sum_{k = 0..n} binomial(n,k)*B(k) and A(n+1) = Sum_{k = 0..n} binomial(n,k)*C(k). This entry gives the sequence C(n).at n=10A143817
• Numbers n such that A003146(n) = floor(alpha^3*n)+1, where alpha = 1.839... is the positive real zero of x^3-x^2-x-1.at n=43A278353