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A066284 a(n) = A066135(4*n).

%I A066284 #18 Jul 18 2017 11:54:11
%S A066284 34,84,34,84,34,194,34,84,34,84,34,228,34,84,34,84,34,194,34,84,34,84,
%T A066284 34,228,34,84,34,84,34,194,34,84,34,84,34,386,34,84,34,84,34,194,34,
%U A066284 84,34,84,34,228,34,84,34,84,34,194,34,84,34,84,34,228,34,84,34,84,34,194
%N A066284 a(n) = A066135(4*n).
%C A066284 a(n) <= 2p, where p = A002586(4n) is the least prime factor of (1 + 16^n). (See the Comment in A066135.) - _Jonathan Sondow_, Nov 23 2012
%H A066284 Michael De Vlieger, <a href="/A066284/b066284.txt">Table of n, a(n) for n = 1..1000</a>
%F A066284 a(n) = Min{x : sigma_4n(x) mod x = 0, x > 1}
%e A066284 First 3 terms correspond to entries of other sequences as follows: a(1)=A046763(2), a(2)=A055712(2), a(3)=A055716(2).
%e A066284 From _Michael De Vlieger_, Jul 17 2017: (Start)
%e A066284 First position of values, with observations pertaining to values for 1 <= n <= 3000:
%e A066284     Value   Position   Observations:
%e A066284     --------------------------------
%e A066284        34     1        All odd.
%e A066284        84     2        In A047235.
%e A066284       194     6        In A017593.
%e A066284       228    12
%e A066284       386    36
%e A066284      1282    72
%e A066284      1538   144
%e A066284      3084   288
%e A066284    147468   576
%e A066284      1956   864
%e A066284   1046532  1152
%e A066284     24578  2304
%e A066284      3252  2880
%e A066284 (End)
%t A066284 Table[m = 2; While[Mod[DivisorSigma[4 n, m], m] > 0, m++]; m, {n, 66}] (* _Michael De Vlieger_, Jul 17 2017 *)
%o A066284 (PARI) a(n) = {n *= 4; my(m = 2); while (sigma(m, n) % m, m++); m;} \\ _Michel Marcus_, Oct 02 2016
%Y A066284 Cf. A066135, A046761, A046762, A046763, A055709-A055717, A007691, A001159.
%K A066284 nonn
%O A066284 1,1
%A A066284 _Labos Elemer_, Dec 11 2001