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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A091340 Amicable numbers with property that each member m of the corresponding amicable pair is divisible by sopfr(m) (the sum of prime factors with repetition, A001414).

Original entry on oeis.org

821921625, 988676775, 4024942087978, 4179223134422, 100733767393275, 110452715806725
Offset: 1

Views

Author

Sven Simon, Dec 31 2003

Keywords

Comments

Both members of the amicable pair appear in the sequence.
Conjecture: sequence is finite (even though there are many known amicable numbers - about 8*10^7 currently).
Sergei Chernykh and the teams @Boinc found a new pair with their still ongoing search in the 21-digit range, 109297847965212832096 with sopfr(m)=118618 and 109392896505354817184 with sopfr(m)=39152. - Sven Simon, Sep 19 2020

Examples

			a(1): 821921625 = 3^2*5^3*7*29*59*61, sopfr(n) = 177 = 3*59.
a(2): 988676775 = 3^2*5^2*71*199*311, sopfr(n) = 597 = 3*199.

Links

Crossrefs

Cf. A001414, A046346, A063990, A259180 (amicable pairs).
Cf. A267076 (amicable pairs that have the same sopfr).
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