20395

Appears in sequences

• Subminimal numbers, from minimal numbers by analogy with subfactorials.at n=54A079717
• Denominators of convergents to the Thue-Morse constant 0.41245403364...at n=10A085395
• Semiprimes (A001358) whose digit reversal is a pentagonal number (A000326).at n=26A115708
• a(n) = least k such that the remainder when 12^k is divided by k is n.at n=12A127820
• Least k such that n^k mod k = n + 1.at n=10A128172
• Number of n-ary words beginning with the first character of the alphabet, that can be built by inserting four doublets into the initially empty word.at n=12A194716
• Number of partitions p = [x(1), ..., x(k)], where x(1) >= x(2) >= ... >= x(k), of n such that max(x(i) - x(i-1)) <= number of distinct parts of p.at n=40A241819
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 817", based on the 5-celled von Neumann neighborhood.at n=26A273648
• a(n) = Sum_{k=1..n} binomial(2*n, k) * sigma(k).at n=5A356341
• a(n) = Sum_{k=2..n} binomial(k,2) * floor(n/k).at n=46A366967