2097146

Appears in sequences

• Numbers k such that phi(k + 6) | sigma(k) + 6.at n=11A015872
• a(n)^2 + 1 is largest prime of the form x^2 + 1 <= 2^n.at n=41A083848
• Binomial transform of [1,1,7,1,7,1,7,1,...].at n=19A131130
• a(n) = round((2^n - n - 1)/4).at n=22A173010
• Expansion of (1+2x)*(1+2*x^2)/((1-x)*(1+x)*(1-2*x^2)).at n=37A185647
• Numbers m for which sigma(m) - m = tau(m)^k for some integer k > 0.at n=12A219668
• Numbers such that none of their prime factors share common 1-bits in the same bit-position and when added (or "ored" or "xored") together, yield a term of A000225 (a binary "repunit").at n=16A235490
• a(n) = 2*a(n-1) + a(n-2) - 2*a(n-3) for n>2, a(0)=-1, a(1)=-2, a(2)=-4.at n=22A254076
• Decimal representation of the n-th iteration of the "Rule 227" elementary cellular automaton starting with a single ON (black) cell.at n=10A267847
• Composite numbers whose sum of proper divisors is a power of 2.at n=28A279731
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 873", based on the 5-celled von Neumann neighborhood.at n=20A284350
• a(n) is the number of trailing zeros in (2^n)!.at n=23A354463
• Records of A112591.at n=19A375235
• Nonprime numbers whose sum of proper divisors is a power of 4.at n=19A383872