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A318251 Lesser 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. 1
6144, 19329024, 939524096, 4026531840, 309237645312, 6146186280960, 52158082842624, 29273397577908224 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The larger numbers in each pair are in A318252.
Analogous to A002025 as A163272 is analogous to A000396.
If p and 4p+1 are primes then 2^(4p-1)*p is in this sequence, therefore if A023212 is infinite then also this sequence is.
The terms were calculated using an extended list of terms of A025487.
LINKS
EXAMPLE
6144 is in the sequence since A074206(6144) = 13312 and A074206(13312) = 6144.
PROG
(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)); a>n && f(a)==n; } \\ Michel Marcus, Sep 26 2018
CROSSREFS
Sequence in context: A251787 A203982 A204626 * A281265 A007992 A033288
KEYWORD
nonn,more
AUTHOR
Amiram Eldar, Aug 22 2018
STATUS
approved

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Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)