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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 Table of n, a(n) for n=1..8. 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 Cf. A023212, A074206, A090866, A163272, A318252. Sequence in context: A251787 A203982 A204626 * A281265 A007992 A033288 Adjacent sequences: A318248 A318249 A318250 * A318252 A318253 A318254 KEYWORD nonn,more AUTHOR Amiram Eldar, Aug 22 2018 STATUS approved

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Last modified September 27 01:21 EDT 2023. Contains 365669 sequences. (Running on oeis4.)