1013760

Appears in sequences

• Droll numbers: numbers > 1 whose sum of even prime factors equals the sum of odd prime factors.at n=32A019507
• Expansion of e.g.f. x^4*exp(x)^2.at n=11A052796
• Number of strings over Z_4 of length n with trace 2 and subtrace 2.at n=11A068790
• a(n) = (n^3 - n)*2^n.at n=9A128960
• a(n) = A203418(n)/A000178(n).at n=8A203420
• 1-quantum transitions in systems of N spin 1/2 particles, in columns by combination indices. Triangle read by rows, T(n, k) for n >= 1 and 0 <= k <= floor((n-1)/2).at n=38A213343
• The number of positive integer sequences of length n with no duplicate substrings (forward or backward) of length greater than 1, no self-adjacent terms, and a minimal product (= A282170(n)).at n=16A284436
• a(n) = phi(A291789(n)).at n=30A291805
• a(n) is the number of subsets of {1..n} that contain exactly 4 odd numbers.at n=22A331419
• Triangle read by rows: T(n,k) = Sum_{j=0..2k} (-1)^j * binomial(2k,j) * (k-j)^(2n).at n=24A387597
• a(n) = Sum_{k=0..floor(n/3)} 2^k * 3^(n-3*k) * binomial(k,3*(n-3*k)).at n=34A392042