49951

Appears in sequences

• Denominators of continued fraction convergents to sqrt(221).at n=9A041413
• Denominators of continued fraction convergents to sqrt(884).at n=13A042709
• a(n) = n^4 - 3*n^2 + 1.at n=15A057722
• Numbers k such that sigma(k) and sigma(k+1) are nontrivial powers (A065496).at n=17A065522
• A Chebyshev S-sequence with Diophantine property.at n=4A078364
• a(n) = (2*n^3 - n^2 - n + 2)/2.at n=37A081441
• Numbers k such that k-1 and k+1 are each the product of exactly 7 primes, counted with multiplicity.at n=12A157487
• T(n,k)=Number of ways to reciprocally link elements of an nXk array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links.at n=47A220738
• Number of ways to reciprocally link elements of an 3Xn array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links.at n=7A220740
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 833", based on the 5-celled von Neumann neighborhood.at n=36A273677
• a(n) = Sum_{k=0..floor(n/2)} binomial(3*k,3*(n-2*k)).at n=15A391903