55237

Appears in sequences

• Number of elements in Z[ i ] whose 'smallest algorithm' is <= n.at n=12A006457
• Last term where no prime sums occur in A161190 in a 4-diagonal set of 24 terms.at n=33A161193
• Irregular triangle read by rows. Properly color the vertices of a simple labeled graph on [n] using exactly n colors c_1<c_2<...<c_n (in other words, use each color exactly once). Orient the edges according to the strict order on the colors. T(n,k) is the number of such graphs with exactly k descents, n>=0, 0<=k<=binomial(n,2).at n=36A381192