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A318251
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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.
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1
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OFFSET
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1,1
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COMMENTS
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The larger numbers in each pair are in A318252.
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.
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LINKS
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EXAMPLE
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6144 is in the sequence since A074206(6144) = 13312 and A074206(13312) = 6144.
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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