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%I #16 May 22 2019 00:04:13
%S 11,321,657,24699,824438641,9331106993,165242994898683,
%T 5626813041698235,210318566007979643,90916134718317480897884289,
%U 206287562744685037912181145873,729990278282182004516138224533969
%N Let M be the n-th Giuga number (see A007850); a(n) = sum of (M/p - 1)/p for primes p dividing M.
%C For the additional Giuga number (not known to be the next term of A007850), 4200017949707747062038711509670656632404195753751630609228764416142557211582098432545190323474818 the corresponding value is 1563694051115215735786664430977202618214176554388873529993304101116913223541171676954379378709457.
%e Prime factors of 30 are 2, 3 and 5: (30/2 - 1)/2 + (30/3 - 1)/3 + (30/5 - 1)/5 = 7 + 3 + 1 = 11.
%p with(numtheory): P:=proc(q) local n,x; x:=[30, 858, 1722, 66198, 2214408306, 24423128562, 432749205173838, 14737133470010574, 550843391309130318, 244197000982499715087866346, 554079914617070801288578559178, 1910667181420507984555759916338506];
%p for n from 1 to nops(x) do print(add((x[n]/k-1)/k,k=factorset(x[n]))); od; end: P(1);
%Y Cf. A007850, A270816.
%K nonn,more
%O 1,1
%A _Paolo P. Lava_, Mar 23 2016
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