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%I #7 Apr 18 2019 16:52:10
%S 1,2,2,5,9,14,42,42,168,504,2520,2531,2543,2556,17892,89460,357840,
%T 357857,357875,357894,3578940,25052580,275578380,275578403,275578427,
%U 275578452,3582519876,10747559628,75232917396,75232917425,451397504550
%N a(0)=1 and for n>0: a(n) = if gcd(a(n-1),n)>1 then lcm(a(n-1),n) else a(n-1)+n.
%C As gcd(a(7-1),7) = gcd(42,7) = 7, a(7) = lcm(a(7-1),7) = a(6)*7/gcd(a(7-1),7) = 42*7/7 = 42 = a(6), are there more n such that a(n+1)=a(n)?
%H Robert Israel, <a href="/A076607/b076607.txt">Table of n, a(n) for n = 0..1145</a>
%p A[0]:= 1:
%p for n from 1 to 100 do
%p if igcd(A[n-1],n) > 1 then A[n]:= ilcm(A[n-1],n)
%p else A[n]:= A[n-1]+n
%p fi
%p od:
%p seq(A[i],i=0..100); # _Robert Israel_, Apr 18 2019
%K nonn
%O 0,2
%A _Reinhard Zumkeller_, Oct 21 2002
%E Corrected by _Robert Israel_, Apr 18 2019
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