21206

Appears in sequences

• Number of nonempty subsets of {1,2,...,n} in which exactly 1/3 of the elements are <= (n-1)/2.at n=17A047172
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/3 of the elements are <= (n-2)/2.at n=17A047183
• Numbers n such that Fibonacci(n) is not squarefree, but for all proper divisors k of n, Fibonacci(k) is squarefree.at n=40A065069
• Sum of the second moments of all partitions of n with weights starting from 1.at n=14A066187
• a(n) = floor(C(n+8,8)/C(n+2,2)).at n=22A084631
• Numbers k such that the first 9 decimal digits of the k-th Fibonacci number is 1-9 pandigital.at n=9A112516
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (-1, 1, 1), (1, -1, 0), (1, 0, 1), (1, 1, -1)}.at n=8A149479
• Monotonic ordering of set S generated by these rules: if x and y are in S then 3xy-x-y is in S, and 2 is in S.at n=18A192529
• Number of nX3 0..1 arrays with exactly floor(nX3/2) elements unequal to at least one king-move neighbor, with new values introduced in row major 0..1 order.at n=10A222323
• Sum over all partitions lambda of n into 3 distinct parts of Product_{i:lambda} prime(i).at n=12A258358