54561

Appears in sequences

• Pisot sequence L(2,7).at n=8A048576
• Powers of three read in base 2.at n=28A211864
• Irregular triangle read by rows: T(n,k) is the number of permutations in C_n (= the 1-cycles in S_n) having k stretching pairs.at n=46A216121
• Pseudoprimes to base 7, written in base 7.at n=22A262104
• Triangular array T(n,k), read by rows: coefficients of strong divisibility sequence of polynomials p(1,x) = 1, p(2,x) = 3 + 3*x, p(n,x) = u*p(n-1,x) + v*p(n-2,x) for n >= 3, where u = p(2,x), v = 1 - 2*x - x^2.at n=31A367301