26231

Appears in sequences

• Number of nondecreasing sequences that are differences of two permutations of 1,2,...,n.at n=9A019589
• Triangular matrix, read by rows, where row k is formed from the first differences of row (k-1) of its matrix square, with an appended '1' for the main diagonal.at n=40A102225
• Semiprimes formed by inserting a semiprime between the semiprime's ordered factors.at n=7A227942
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 931", based on the 5-celled von Neumann neighborhood.at n=26A273790