20678

Appears in sequences

• a(n) is the smallest number greater than a(n-1) such that in a(0) through a(n) no digit occurs more than once more than any other digit.at n=34A095204
• Row sums of triangle A101224, which is related to the Flavius sieve (A000960).at n=28A101105
• Position where n (presumably) appears the last time in A032531, or 0 if n keeps appearing.at n=0A107263
• Coefficient array of orthogonal polynomials P(n,x)=(x-2n)*P(n-1,x)-(2n-3)*P(n-2,x), P(0,x)=1,P(1,x)=x-2.at n=23A178120
• a(n) is the smallest number greater than a(n-1) such that in a(1) through a(n) no digit occurs more than once more than any other digit, starting with a(1) = 1.at n=34A248651
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 14", based on the 5-celled von Neumann neighborhood.at n=41A269709
• Positions of 0's in A330314.at n=23A330325
• a(n) = Sum_{k=0..n} binomial(k+5,5) * binomial(2*k,2*n-2*k).at n=6A382472