3922632451

Appears in sequences

• a(n) = (9^n - 1)/8.at n=11A002452
• Coloring a circuit with 4 colors.at n=21A006342
• Cyclotomic polynomials at x=9.at n=11A019327
• Cyclotomic polynomials at x=-9.at n=22A020508
• Gaussian binomial coefficients [ n,10 ] for q = 9.at n=1A022261
• Base-3 digits are, in order, the first n terms of the periodic sequence with initial period 1,0.at n=20A033113
• a(n) = Sum_{j=0..10} n^j.at n=9A060885
• Numbers of the form (9^{mr}-1)/(9^r-1) for positive integers m, r.at n=27A076288
• a(n) = Sum_{k=0..floor(n/2)} binomial(n-k, k-1)*2^(n-k-1)*(3/2)^(k-1).at n=22A099583
• If n mod 2 = 0 then (3^(n+3)-19)/8 else (3^(n+3)-1)/8.at n=19A116973
• a(n) = (3^n-1)/2 if n odd, (3^n-1)/8 if n even.at n=22A152298
• A threes sequence that gets more even factors out: a(n) = (3^n - 1)*(3^n + 1)/2^(4 - (n mod 2)).at n=11A152299
• Sum n^k, k=0..n+1.at n=8A173468
• Cipolla pseudoprimes to base 3: (9^p-1)/8 for any odd prime p.at n=3A210461
• Fermat pseudoprimes to base 3 of the form (3^(4*k + 2) - 1)/8.at n=4A217853
• Expansion of 1/((x-1)*(3*x-1)*(3*x^2+1)).at n=20A239577
• a(n) = p(0,n), where p(x,n) is the strong divisibility sequence of polynomials based on sqrt(3) as in A327321.at n=21A329008
• Triangular numbers that are palindromes in base 3.at n=18A350990
• Cogrowth sequence of the 16-element Pauli group C4 o D4 = <S,T,U | s^4, T^2, U^2, S^2(TU)^2, [S,T], [S,U]>.at n=11A377943