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%I #15 Sep 18 2022 15:55:55
%S 1,3,4,3,6,6,8,3,4,8,12,6,14,10,9,3,18,6,20,8,11,14,24,6,6,16,4,10,30,
%T 11,32,3,15,20,13,6,38,22,17,8,42,13,44,14,9,26,48,6,8,8,21,16,54,6,
%U 17,10,23,32,60,11,62,34,11,3,19,17,68,20,27,15,72,6,74,40,9,22,19,19,80,8
%N 1 + the sum of the distinct primes dividing n.
%C Number of maximal subgroups in dihedral group of order 2n. - _Eric M. Schmidt_, Oct 14 2014
%H Neville Holmes, <a href="http://www.comp.utas.edu.au/users/nholmes/sqncs/index.htm#A074372">Integer Sequences</a>
%F a(n) = 1 + A008472(n).
%e 2: 3 (1+2); 3: 4 (1+3); 4: 3 (1+2); 5: 6 (1+5); 6: 6 (1+2+3); ...
%p with(numtheory): a:=proc(n) local F: F:=convert(factorset(n),list): 1+sum(F[j],j=1..nops(F)) end: seq(a(n),n=1..90); # _Emeric Deutsch_, Mar 12 2005
%t Rest[ Range[0, 20] CoefficientList[ Log[E, Series[(1/(1 - x)) Product[ 1/(1 - x^Prime[j]), {j, 200}], {x, 0, 20}]], x]] (* _Robert G. Wilson v_, Aug 16 2011 *)
%t Join[{1},Array[1+Total[FactorInteger[#][[All,1]]]&,80,2]] (* _Harvey P. Dale_, Sep 18 2022 *)
%Y Cf. A001414, A008472, A036288.
%K easy,nonn
%O 1,2
%A _W. Neville Holmes_, Aug 22 2002
%E Corrected and extended by _Emeric Deutsch_, Mar 12 2005