369512

Appears in sequences

• a(n) = Sum_{j=0..n} (n+j)*binomial(n+j,j).at n=8A002737
• Expansion of (1-4*x)^(19/2).at n=21A020931
• Twice central binomial coefficients.at n=10A028329
• a(n) = Sum_{j=0..n} A047072(j, n-j).at n=21A047073
• Number of n-step walks on a line starting from the origin but not returning to it.at n=21A063886
• Denominators of row sums in triangle described in A093412.at n=19A093419
• a(0) = 1; for n>0, if gcd(a(n-1),n) = 1 then a(n) = n*a(n-1) else a(n) = least integer multiple of a(n-1)/n.at n=19A094299
• Denominator of -3*n + 2*(1+n)*HarmonicNumber(n).at n=20A096620
• A Catalan transform of (1 + 2*x)/(1 - 2*x).at n=10A100320
• Denominators of third-order harmonic numbers (defined by Conway and Guy, 1996).at n=18A124838
• Denominator of Sum_{k=1..n} k*H_{n+k} where H_m = Sum_{i=1..m} 1/i.at n=20A144655
• Denominator of the Harary number for the cycle graph C_n.at n=41A160047
• Denominator of the Harary number for the path graph P_n.at n=20A160049
• Triangle T(n,i) whose n-th row gives the number of numbers in any prime(n)# consecutive numbers whose smallest prime factor is prime(n-i+1).at n=32A174909
• a(n) = number of n-lettered words in the alphabet {1, 2} with as many occurrences of the substring (consecutive subword) [1, 1] as of [2, 2].at n=22A182027
• Triangle associated with the set S of squares {0,1,4,9,16,...}.at n=60A186432
• Number of arrays of n+2 integers in -1..1 with sum zero and the sum of every adjacent pair being odd.at n=37A202069
• Z-sequence for the Riordan triangle A111125.at n=10A217477
• Number of permutations of length n such that numbers at odd positions are monotone and numbers at even positions are also monotone.at n=19A257546
• Triangle T(n,k) read by rows: T(n,k) = A005867(k-1)*A002110(n)/A002110(k).at n=31A293558