597871

Appears in sequences

• a(n) = (9^n - 1)/8.at n=7A002452
• Numerators of central difference coefficients M_{3}^(2n+1).at n=6A002673
• Coloring a circuit with 4 colors.at n=13A006342
• Triangle of central factorial numbers 4^k T(2n+1, 2n+1-2k).at n=34A008958
• Cyclotomic polynomials at x=9.at n=7A019327
• Cyclotomic polynomials at x=-9.at n=14A020508
• Triangle of Gaussian binomial coefficients [ n,k ] for q = 9.at n=29A022173
• Triangle of Gaussian binomial coefficients [ n,k ] for q = 9.at n=34A022173
• Gaussian binomial coefficients [ n,6 ] for q = 9.at n=1A022257
• Base-3 digits are, in order, the first n terms of the periodic sequence with initial period 1,0.at n=12A033113
• a(n) = 1111111 in base n.at n=8A053716
• Sum of squares of divisors of square numbers.at n=26A065827
• Numbers of the form (3^{mr}-1)/(3^r-1) for positive integers m, r.at n=34A076270
• Numbers of the form (9^{mr}-1)/(9^r-1) for positive integers m, r.at n=14A076288
• Odd composites with increasing proportion of nontrivial non-witnesses of compositeness by the Miller-Rabin primality test.at n=15A090659
• 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=21A096043
• a(n) = Sum_{k=0..floor(n/2)} binomial(n-k, k-1)*2^(n-k-1)*(3/2)^(k-1).at n=14A099583
• Records in A111273.at n=25A113732
• If n mod 2 = 0 then (3^(n+3)-19)/8 else (3^(n+3)-1)/8.at n=11A116973
• a(n) = ((n+1)^(n-1) - 1)/n.at n=7A125598