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A324708
Lesser of tri-unitary amicable numbers pair: numbers (m, n) such that tsigma(m) = tsigma(n) = m + n, where tsigma(n) is the sum of the tri-unitary divisors of n (A324706).
9
114, 594, 1140, 5940, 8640, 10744, 12285, 13500, 44772, 60858, 62100, 67095, 67158, 79296, 79650, 79750, 118500, 142310, 143808, 177750, 185368, 298188, 308220, 356408, 377784, 462330, 545238, 600392, 608580, 609928, 624184, 635624, 643336, 643776, 669900
OFFSET
1,1
COMMENTS
The larger counterparts are in A324709.
LINKS
EXAMPLE
114 is in the sequence since it is the lesser of the amicable pair (114, 126): tsigma(114) = tsigma(126) = 114 + 126.
MATHEMATICA
f[p_, e_] := If[e == 3, (p^4-1)/(p-1), If[e==6, (p^8-1)/(p^2-1), p^e+1]]; tsigma[1]=1; tsigma[n_]:= Times @@ f @@@ FactorInteger[n]; s[n_] := tsigma[n] - n; seq={}; Do[m=s[n]; If[m>n && s[m]==n, AppendTo[seq, n]] , {n, 1, 700000}]; seq
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 11 2019
STATUS
approved