21006

Appears in sequences

• Number of non-isomorphic (i.e., defined up to a rotation and a reflection) maximal independent sets of the n-cycle graph having 2n isomorphic representatives.at n=51A127683
• Starts of runs of 3 consecutive Niven numbers in base 2 (A049445).at n=10A330932
• Array read by antidiagonals: A(n,k) is the number of nonnegative integer matrices with k distinct columns and any number of distinct nonzero rows with column sums n and rows in decreasing lexicographic order.at n=41A331160
• Number of distinct sums i^3 + j^3 + k^3 + l^3 for 1<=i<=j<=k<=l<=n.at n=27A374714