1048568

Appears in sequences

• Numbers n such that uphi(sigma(n)) = n, where the uphi is the unitary phi function A047994.at n=33A030164
• Number of subsets of {1,2,3,...,n} that sum to 0 mod 64.at n=26A068045
• Numerators of coefficients in expansion of x^-2*(1-exp(-2*x))^2.at n=16A104042
• Triangle read by rows: row n lists the divisors of n-th perfect number A000396(n) that are multiples of n-th Mersenne prime A000668(n).at n=33A139247
• a(n) = 8*(2^n - 1).at n=16A159741
• Positions of zeros in A165477.at n=16A165478
• Row sums of triangle A166455.at n=19A166456
• Monotonic ordering of nonnegative differences 4^i-8^j, for 40>= i>=0, j>=0.at n=39A192167
• Non-unitary amicable numbers.at n=27A259037
• Larger of a non-unitary amicable pair.at n=13A259039
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 121", based on the 5-celled von Neumann neighborhood.at n=19A278957
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 259", based on the 5-celled von Neumann neighborhood.at n=19A280369
• Decimal representation of the diagonal from the corner to the origin of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 307", based on the 5-celled von Neumann neighborhood.at n=19A287598
• a(n) = 2^n - (2^(n-1) mod n), where "mod" is the nonnegative remainder operator.at n=19A320465
• Numbers k such that uphi(usigma(k)) = k where usigma is the sum of unitary divisors of k (A034448) and uphi is the unitary totient function (A047994).at n=43A329855
• Nonunitary superperfect numbers: numbers k such that nusigma(nusigma(k)) = k, where nusigma(k) = sigma(k) - usigma(k) is the sum of nonunitary divisors of k (A048146).at n=31A329884
• Numbers that are either already perfect, or a perfect number is eventually reached if we start doubling them.at n=29A341622