22990

Appears in sequences

• a(n) = a(n-1) + a(n-6), with a(i) = 1 for i = 0..5.at n=43A005708
• Expansion of 1/(1 - x^6 - x^7 - x^8 - ...).at n=49A017900
• a(n) = Sum_{d|n} sigma(n/d)*d^3.at n=26A027847
• Integer part of log(n^n)^(1 + log(log(1 + n))).at n=27A062479
• a(n) = n*(n+1)*(n^2 + 2)/6.at n=19A071239
• a(n) = (1/24)*(sigma_3(2*n-1) - sigma_1(2*n-1)).at n=40A081861
• a(n) = n*(n+1)*(20*n-17)/6.at n=19A172117
• Number of real singularities on a family of degree-3n algebraic surfaces.at n=12A200048
• Number of 4 X n -1,1 arrays such that the sum over i=1..4,j=1..n of i*x(i,j) is zero and rows are nondecreasing (ways to put n thrusters pointing east or west at each of 4 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).at n=44A225311
• Numbers whose square can be written as sum of at least 3 consecutive triangular numbers in two ways.at n=8A256000
• a(n) = Sum_{d|n} d^3*A000593(n/d).at n=26A288419
• G.f.: Product_{m>0} (1+x^m+2!*x^(2*m)).at n=41A293204
• G.f. A(x) satisfies: A(x) = x + x^2 * exp(3 * Sum_{k>=1} (-1)^(k+1) * A(x^k) / k).at n=10A345244
• a(n) = Sum_{k=0..floor(n/3)} binomial(2*n-5*k-1,k).at n=22A373654
• Number of compositions of 6*n-5 into parts 1 and 6.at n=7A373960
• Expansion of (1/x) * Series_Reversion( x * (1 - x - x^5 / (1 - x)) ).at n=10A389405