1811939328

Appears in sequences

• a(n) = n*2^(n-1).at n=27A001787
• a(n) = lcm(n, 2^(n-1)).at n=26A014964
• a(n) = (3^3)*4^(n-3) with a(0)=1, a(1)=1 and a(2)=7.at n=16A056120
• Expansion of ((1-x)/(1-2*x))^3.at n=25A058396
• a(n) = 2^(2*n)*(2*n+1).at n=13A058962
• Composites of form prime-1 containing a record number of prime factors.at n=23A066632
• Refactorable numbers x, such that quotient x/A000005(x) equals a power of 2.at n=31A078541
• 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=29A079352
• Start with the sequence [1, 1/2, 1/3, ..., 1/n]; form new sequence of n-1 terms by taking averages of successive terms; repeat until reach a single number F(n); a(n) = denominator of F(n).at n=26A090634
• Expansion of g.f. (1-4*x+5*x^2)/(1-2*x)^2.at n=28A097067
• Binomial transform of A004526.at n=28A139756
• a(n) is the smallest positive integer m with exactly n zeros in its binary representation and with n represented in binary as a substring of the binary representation of m.at n=26A147761
• a(n) = 27*2^n.at n=26A175806
• Number of (possibly overlapping) occurrences of the subword given by the binary expansion of n in all binary words of length n.at n=31A228612
• Number of (possibly overlapping) occurrences of the subword given by the binary expansion of n in all binary words of length n.at n=32A228612
• Smallest number of the form 11*m+1 with exactly n prime factors, counted with multiplicity.at n=29A230123
• a(n) = 3*n*2^(3*n-1).at n=9A230539
• a(n) = Product_{k=1..n} d(2*k - 1), where d() is the number of divisors function A000005.at n=22A334764
• 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=29A370935
• Determinant of the matrix [Jacobi(i^2+5*i*j+5*j^2,2*n+1)]_{1<i,j<2*n}, where Jacobi(a,m) denotes the Jacobi symbol (a/m).at n=8A372394