20510

Appears in sequences

• Weird numbers: abundant (A005101) but not pseudoperfect (A005835).at n=36A006037
• McKay-Thompson series of class 6b for the Monster group.at n=6A007261
• Numbers that are sums of 2 or more consecutive squares in more than 1 way.at n=28A062681
• Unitary weird numbers: unitary abundant (A034683) but not unitary pseudoperfect (A293188).at n=34A064114
• Numbers that are the sum of one or more consecutive squares in more than one way.at n=35A130052
• Number of (w,x,y,z) with all terms in {1,...,n} and w<|x-y|+|y-z|.at n=29A212692
• Triangle read by rows: R*(n,k) (n>=2, k from 2 to n-1 or to 2 if n = 2), where R*(n,k) = number of trees with n nodes and k unlabeled end-nodes.at n=62A213262
• Number of (n+1) X (4+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=6A250579
• Number of (n+1)X(7+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=3A250582
• Number of Catalan words of length n avoiding the pattern 000.at n=14A307464
• Numbers that can be written as the sum of four or more consecutive squares in more than one way.at n=19A307937
• Nonexponential weird numbers: nonexponential abundant numbers (A348604) that are not equal to the sum of any subset of their nonexponential divisors.at n=30A348631
• (1+e)-weird numbers: (1+e)-abundant numbers k such that no subset of the aliquot (1+e)-divisors of k sums to k.at n=31A349285
• a(n) is the sum of all integers of the form k^2 + 1 whose greatest prime factor is A002313(n), the n-th prime not congruent to 3 mod 4.at n=5A379347
• Expansion of g/(1 - x^3*g^2), where g = 1+x*g^2 is the g.f. of A000108.at n=10A391031