20046

Appears in sequences

• Positive numbers k such that k and 3*k are anagrams in base 7 (written in base 7).at n=28A023069
• Base-4 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,3,2.at n=7A037681
• a(n) = Sum_{k=0..n} A136595(n,k)*n^k.at n=6A136588
• 29-gonal numbers: a(n) = n*(27*n-25)/2.at n=39A255187
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 611", based on the 5-celled von Neumann neighborhood.at n=25A273214