34220

Appears in sequences

• Sum of the first n even squares: a(n) = 2*n*(n+1)*(2*n+1)/3.at n=29A002492
• Binomial coefficient C(4n, n-12).at n=3A004342
• Binomial coefficient C(5*n,n-9).at n=3A004351
• Binomial coefficient C(6n,n-7).at n=3A004362
• Dodecahedral numbers: a(n) = n*(3*n - 1)*(3*n - 2)/2.at n=20A006566
• Even tetrahedral numbers.at n=43A015220
• Binomial coefficients C(n,57).at n=3A017721
• Binomial coefficients C(60,n).at n=3A017776
• Values of C(n,3) which can be written as C(x,3) + C(y,3).at n=3A034404
• Let D(n) = n*(9*n^2-9*n+2)/2 then a(k+1) = D(a(k)) and a(0) = 1.at n=2A099187
• Binomial(binomial(2*n,n)*n,n).at n=3A119552
• 1/6 of product of three numbers: n-th prime, previous and following number.at n=16A127920
• Tetrahedral numbers k*(k+1)*(k+2)/6 such that exactly one of k, k+1, and k+2 is prime.at n=33A144521
• a(n) = 25*n^2 - 5.at n=36A158446
• First differences of A160379.at n=33A163989
• a(n) = floor(n^(3/2))*floor(1 + n^(3/2))*floor(2 + n^(3/2))/6.at n=14A185592
• The number of unordered pairs (f,g) of functions from {1..n} to itself such that fg=gf (i.e., f(g(i))=g(f(i)) for all i) where f and g are distinct.at n=4A254570
• Irregular triangle read by rows: T(n,k) = number of size k subsets of S_n that remain unchanged by reverse.at n=45A277080
• a(n) = (5*n + 3)*(5*n + 4)*(5*n + 5)/6.at n=11A300522