21370

Appears in sequences

• Number of permutations of length n which avoid the patterns 1234, 1243, 2431.at n=9A116840
• Maximum number of partitions of n into exactly k parts, each <= k. a(n) is maximum in each row of A157044.at n=55A157046
• Number of partitions of 1 into up to n powers of 1/2.at n=18A173404
• Number of distinct functions f representable as x -> x^x^...^x with n x's and parentheses inserted in all possible ways giving result f(0)=1, with conventions that 0^0=1^0=1^1=1, 0^1=0.at n=14A222380
• The number of permutations of length n in a particular geometric grid class.at n=10A226433
• G.f. satisfies: A(x) = A(x^2 + 2*x^3)/(1-x).at n=16A251581
• Expansion of 1/((1-x)*(1-2*x^2)*(1-3*x^3)).at n=21A291986
• Number of odd parts in the partitions of n into 9 parts.at n=41A309656
• Number of integer solutions (a_1, a_2, ... , a_8) to the equation a_1^2 + 2*a_2^2 + ... + 8*a_8^2 = 3*n.at n=21A320243