228480

Appears in sequences

• Array by antidiagonals: Number of planar lattice walks of length 3n+2k starting at (0,0) and ending at (k,0), remaining in the first quadrant and using only NE,W,S steps.at n=31A098273
• Number of length-n 0..6 arrays connected end-around, with no sequence of L<n elements immediately followed by itself (periodic "squarefree").at n=6A215226
• Number of length-7 0..k arrays connected end-around, with no sequence of L<n elements immediately followed by itself (periodic "squarefree").at n=5A215230
• Numbers k for which sigma(k)/k - 6/7 is an integer.at n=3A218413
• Triangle S(n,k) by rows: coefficients of 4^((n-1)/2)*(x^(1/4)*d/dx)^n when n is odd, and of 4^(n/2)*(x^(3/4)*d/dx)^n when n is even.at n=38A223170
• Triangle S(n,k) by rows: coefficients of 4^((n-1)/2)*(x^(1/4)*d/dx)^n when n=1,3,5,...at n=18A223527
• Fifth differences of 7th powers (A001015).at n=11A259907
• Hemi-imperfect numbers: numbers such that the denominator of k/A206369(k) is equal to 2.at n=12A295236
• T(n, k) = [x^k] 2^n*(Euler(n, x) - Euler(n, x/2)), where Euler(n, x) are the Euler polynomials. Triangle read by rows, T(n, k) for 0 <= k <= n.at n=58A342315
• Numbers k for which k * gcd(sigma(k), A003961(k)) is equal to sigma(k) * gcd(k, A003961(k)), where A003961 shifts the prime factorization one step towards larger primes, and sigma is the sum of divisors function.at n=6A349745
• Number of n node tournaments that have exactly two circular triads.at n=4A357242
• Numbers whose infinitary divisors have a mean infinitary abundancy index that is larger than 2.at n=25A374788