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 A126174 Smaller member of an augmented infinitary amicable pair. 8
 1252216, 1754536, 2166136, 2362360, 6224890, 7626136, 7851256, 9581320, 12480160, 12494856, 13324311, 15218560, 15422536, 19028296, 29180466, 36716680, 37542190, 40682824, 45131416, 45495352, 56523810, 67195305, 71570296, 80524665, 89740456, 93182440, 101304490 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A divisor of n is called infinitary if it is a product of divisors of the form p^{y_a 2^a}, where p^y is a prime power dividing n and sum_a y_a 2^a is the binary representation of y. LINKS Amiram Eldar, Table of n, a(n) for n = 1..276 Jan Munch Pedersen, Tables of Aliquot Cycles. FORMULA The values of m for which isigma(m)=isigma(n)=m+n-1, where m 0, 1 + p^(2^(m - j)), 1], {j, 1, m}]]; infs[n_] := Times @@ (fun @@@ FactorInteger[n]) - n; s = {}; Do[k = infs[n] + 1; If[k > n && infs[k] == n - 1, AppendTo[s, n]], {n, 2, 10^9}]; s (* Amiram Eldar, Jan 20 2019 *) CROSSREFS Cf. A126169, A049417, A126168, A037445, A126170, A126171, A126173, A126175, A126176. Sequence in context: A251156 A210132 A251118 * A186089 A208489 A257268 Adjacent sequences:  A126171 A126172 A126173 * A126175 A126176 A126177 KEYWORD hard,nonn AUTHOR Ant King, Dec 23 2006 EXTENSIONS a(9)-a(27) from Amiram Eldar, Jan 20 2019 STATUS approved

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Last modified May 25 19:19 EDT 2022. Contains 354071 sequences. (Running on oeis4.)