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Smallest number with exactly A025475(n) divisors.
1

%I #11 Jul 12 2024 10:16:46

%S 1,6,24,36,120,1296,900,840,46656,7560,44100,60466176,810000,83160,

%T 2176782336,2822400,1081080,2821109907456,729000000,101559956668416,

%U 17297280,131621703842267136,1944810000,341510400

%N Smallest number with exactly A025475(n) divisors.

%C Note that 2^(n-1) has n divisors. - _David Wasserman_, Sep 09 2002

%H Amiram Eldar, <a href="/A065743/b065743.txt">Table of n, a(n) for n = 1..285</a>

%F a(n) = A005179(A025475(n)).

%t a = Table[ 0, {1024} ]; Do[ b = DivisorSigma[ 0, n]; If[ b < 1025 && a[[b]] == 0, a[[b]] = n], {n, 1, 10^8/2} ]; a[[ Select[ Range[2, 1024], !PrimeQ[ # ] && Mod[ #, # - EulerPhi[ # ]] == 0 & ] ]]

%Y Cf. A005179, A025475, A037992, A003680.

%K nonn

%O 1,2

%A _Labos Elemer_, Nov 15 2001

%E More terms from _David Wasserman_, Sep 09 2002