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%I #12 Aug 05 2023 04:12:37
%S 12,40,70,88,1888,4030,5830,8925,32128,32445,78975,442365,521728,
%T 1848964,8378368,34359083008,66072609790
%N Admirable numbers such that the subtracted divisor is prime.
%C 549753192448 is also a term. - _Donovan Johnson_, Sep 08 2012
%e a(2) = 40 because 1+2+4+8+10+20-5 = 40 and the subtracted divisor is prime.
%t q[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2] && PrimeQ[ab/2]; Select[Range[2*10^6], q] (* _Amiram Eldar_, Aug 05 2023 *)
%Y Cf. A111592.
%K nonn,more
%O 1,1
%A _Jason Earls_, Aug 13 2005
%E a(15) from _Donovan Johnson_, Sep 27 2008
%E a(16)-a(17) from _Donovan Johnson_, Sep 08 2012
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