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A307963 Larger of coreful amicable numbers pair: numbers (m, n) such that csigma(m) = csigma(n) = m + n, where csigma(n) is the sum of the coreful divisors of n (A057723). 4
2218040, 4924700, 6654120, 15526280, 14774100, 28834520, 37706680, 42142760, 34472900, 46578840, 51014920, 64323160, 68759240, 64021100, 82067480, 86503560, 90939640, 95375720, 104247880, 83719900, 113120040, 117556120, 93569300, 126428280, 103418700, 130864360 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The terms are ordered according to the their lesser counterparts (A307962).
LINKS
MATHEMATICA
f[p_, e_] := (p^(e+1)-1)/(p-1)-1; csigma[1]=1; csigma[n_] := Times @@ (f @@@ FactorInteger[n]); s={}; Do[m = csigma[n] - n; If[m > n && csigma[m] - m == n, AppendTo[s, m]], {n, 1, 10^8}]; s
CROSSREFS
Sequence in context: A254803 A254810 A253819 * A172802 A172851 A250980
KEYWORD
nonn
AUTHOR
Amiram Eldar, May 08 2019
STATUS
approved

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Last modified July 23 19:43 EDT 2024. Contains 374553 sequences. (Running on oeis4.)