226492416

Appears in sequences

• Denominators of Taylor series expansion of arcsin(x). Also arises from arccos(x), arccsc(x), arcsec(x), arcsinh(x).at n=13A002595
• Coefficient triangle of polynomials (falling powers) related to convolutions of A002605(n), n>=0, (generalized (2,2)-Fibonacci). Companion triangle is A073403.at n=19A073404
• Coefficient triangle of polynomials (rising powers) related to convolutions of A002605(n), n>=0, (generalized (2,2)-Fibonacci). Companion triangle is A073405.at n=16A073406
• a(1)=1, then a(n)=3*a(n-1) if n is already in the sequence, a(n)=2*a(n-1) otherwise.at n=26A079352
• a(n) = n*2^(n-4).at n=23A079859
• a(0) = a(1) = 1; for n > 1, a(n) = (n+2)*2^(n-2).at n=25A087447
• a(1) = 1; a(n+1) = a(n) * k(n), where k(n) is the number of elements of {a(j)}, 1<=j<=n, which are <= n.at n=16A094590
• Smallest number beginning with 2 and having exactly n prime divisors counted with multiplicity.at n=25A106422
• First differences of A129952.at n=25A129953
• a(n) = 27*2^n.at n=23A175806
• Denominators of partial products of a Hardy-Littlewood constant.at n=7A191997
• Number of n X 2 0..2 arrays with new values 0..2 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).at n=13A208428
• Expansion of 1/Sum_{k>=0} A000326(k+1)*x^k.at n=26A296775
• The least number of the form 2^i*3^j (i, j >= 0) which can be represented as a product of the greatest number of distinct positive integers in exactly n ways.at n=39A338261
• a(n) is the first term of A351048 with n prime factors, counted with multiplicity, or 0 if there is no such term.at n=26A370935
• Triangle read by rows: T(n,k) is the number of labeled magmas with n elements whose center contains k elements.at n=11A391154