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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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A318252 Larger of amicable numbers pair (m, n) such that n = H(m) and m = H(n) where H(n) = A074206(n) is the number of ordered factorizations of n.

Original entry on oeis.org

13312, 81551360, 1946157056, 128580583424, 12695923326976, 33590071001088, 2182874178519040, 59672695062659072
Offset: 1

Views

Author

Amiram Eldar, Aug 22 2018

Keywords

Comments

The lesser numbers in each pair are in A318251.
Analogous to A002046 as A163272 is analogous to A000396.
If p and 4p+1 are primes then 2^(4p-2)*(4p+1) is in this sequence.

Examples

			13312 is in the sequence since A074206(13312) = 6144 and A074206(6144) = 13312.

Crossrefs

Cf. A023212, A074206, A090866, A163272, A318251.

Programs

  • PARI
    f(n) = if( n<2, n>0, my(A = divisors(n)); sum(k=1, #A-1, f(A[k])));
isok(n)={my(a=f(n)); aMichel Marcus, Sep 26 2018
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Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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