37512

Appears in sequences

• a(n) = floor(Fibonacci(n)/2).at n=25A004695
• Coordination sequence for {A_5}* lattice.at n=11A008533
• a(n) = C(n-1,1) + C(n-3,3) + ... + C(n-2*m-1,2*m+1), where m = floor((n-2)/4).at n=22A024490
• a(n) = (F(3*n+1) - 1)/2, where F=A000045 (the Fibonacci sequence).at n=8A049651
• Number of palindromes of length n and containing the digit 1 (or any other fixed nonzero digit).at n=8A050686
• Number of palindromes of length n and containing the digit 1 (or any other fixed nonzero digit).at n=9A050686
• Numbers k such that sopf(k) = 2*sopf(k+1), where sopf(k) = A008472.at n=32A064112
• First member of the Diophantine pair (m,k) that satisfies 5*(m^2 + m) = k^2 + k; a(n) = m.at n=8A077259
• Number of "9ish numbers" with n digits.at n=4A088924
• a(0)=1; a(n) = sigma_1(n) + sigma_3(n).at n=32A092345
• Expansion of (1+x)/((1+x+x^2)(1-x-x^2)).at n=23A093040
• Row sums of triangle A099510, so that a(n) = Sum_{k=0..n} coefficient of z^k in (1 + 2*z + z^2)^(n-[k/2]), where [k/2] is the integer floor of k/2.at n=11A099511
• A transform of (1-x)/(1-2x).at n=22A099517
• Table read by rows giving the coefficients of general sum formulas of n-th sums of Bell numbers (A005001). The k-th row (k>=1) contains T(i,k) for i=1 to 2*k and k=1 to n-3, where T(i,k) satisfies Sum_{q=1..n} Bell(q) = 1 + C(n,2) + Sum_{k=1..n-3} Sum_{i=1..2*k} T(i,k) * C(n-k-2,1).at n=24A102735
• Define a(1)=0, a(2)=2 then a(n) = 3*a(n-1) - a(n-2), a(n+1) = 3*a(n)-a(n-1) and a(n+2) = 3*a(n+1) - a(n) + 2.at n=11A105073
• Expansion of g.f. (1+x)^2/((1 + x + x^2)*(1 + x - x^2)).at n=26A106511
• Number of different possible rows (or columns) in an n X n crossword puzzle.at n=22A130578
• Number of 1-sided strip polypons with n cells.at n=32A151532
• a(n) = (A000045(n)-A173432(n))/2.at n=24A173434
• a(2k) = floor(F(k)/2), a(2k+1) = ceiling(F(k)/2), where F = A000045 is the Fibonacci sequence.at n=50A173673