5380840

Appears in sequences

• a(n) = (9^n - 1)/8.at n=8A002452
• Coloring a circuit with 4 colors.at n=15A006342
• Triangle of central factorial numbers 4^k T(2n+1, 2n+1-2k).at n=43A008958
• Gaussian binomial coefficients [ n,7 ] for q = 9.at n=1A022258
• Base-3 digits are, in order, the first n terms of the periodic sequence with initial period 1,0.at n=14A033113
• a(n) = n^7 + n^6 + n^5 + n^4 + n^3 + n^2 + n + 1.at n=9A053717
• a(n) = (n^(n-1) - 1)/(n-1) for n>1, a(1) = 0.at n=8A060072
• (Nearest integer to n^6/36) / 2.at n=26A061005
• Numbers of the form (3^{mr}-1)/(3^r-1) for positive integers m, r.at n=40A076270
• Numbers of the form (9^{mr}-1)/(9^r-1) for positive integers m, r.at n=16A076288
• Triangle read by rows: T(n,k) = (n+1,k)-th element of (M^9-M)/8, where M is the infinite lower Pascal's triangle matrix, 1<=k<=n.at n=28A096043
• a(n) = Sum_{k=0..floor(n/2)} binomial(n-k, k-1)*2^(n-k-1)*(3/2)^(k-1).at n=16A099583
• Modulo 2 binomial transform of 3^n.at n=14A100307
• If n mod 2 = 0 then (3^(n+3)-19)/8 else (3^(n+3)-1)/8.at n=13A116973
• Triangle read by rows: T(n,k) = value of the n-th repunit in base (k+1) representation, 1<=k<=n.at n=35A125118
• a(n) = floor(9^n/n).at n=7A129799
• a(n) = (3^n-1)/2 if n odd, (3^n-1)/8 if n even.at n=16A152298
• Triangle of scaled central factorial numbers, T(n,k) = A008958(n,n-k).at n=37A160562
• T(n,k) = (k^n)*U(n, (1/k + k)/2), where U(n,x) is the n-th Chebyshev polynomial of the second kind, square array read by antidiagonals upward (n >= 0, k >= 1).at n=47A173588
• Triangle generated by T(n,k) = q^k*T(n-1, k) + T(n-1, k-1), with q=3.at n=37A176243