52590

Appears in sequences

• a(n) = Sum_{k=0..2n} (k+1) * A026568(n, k).at n=9A027281
• Half the number of n X n X n triangular binary arrays with each element having no more than two neighbors unequal to itself.at n=13A183276
• Number of rooted 2-connected 4-regular planar maps, which may have loops, with n inner faces.at n=6A318101
• Starts of runs of 3 consecutive Niven numbers in base 2 (A049445).at n=24A330932