270415600

Appears in sequences

• a(n) = 4*(2n+1)!/n!^2.at n=12A002011
• a(n) = (n+1)*binomial(n+1,13).at n=13A027773
• Sum of squared terms in rows of triangle A152547: a(n) = Sum_{k=0..C(n,[n/2])-1} A152547(n,k)^2.at n=25A152548
• Lexicographically earliest sequence such that for any n>1, n=u*v, where u/v = a(n)/a(n-1) in reduced form.at n=24A260850
• A260850 sorted into increasing order and duplicates omitted.at n=27A370974
• a(n) = n*binomial(n, n/2) if n is even otherwise 2^(n-1)*binomial(n-1, (n-1)/2).at n=26A389423