51998

Appears in sequences

• Semiprimes (A001358) whose digit reversal is a pentagonal number (A000326).at n=35A115708
• Row sums of triangle A179901.at n=29A179902
• Number of n X 3 nonnegative integer arrays each row and column an ascent sequence (interior element no greater than one plus up-steps preceding it) and the lower right element equal to min(n,3)-1.at n=8A202730
• T(n,k) = Number of n X k nonnegative integer arrays with each row and column an ascent sequence (interior element no greater than one plus up-steps preceding it) and the lower right element equal to min(n,k)-1.at n=57A202735
• G.f. A(x) satisfies: A( x^2*A(x) - A(x)^4 ) = x^3.at n=7A292928
• Number of separable partitions of n in which the number of distinct (repeatable) parts is > 4.at n=44A325719