Let $\phi(n)$ denote the totient-function

Is the only solution of $$\phi(n)=\phi(n+1)=\phi(n+2)$$ $n=5186$ ? I did not find another solution upto $n=10^8$


Per OEIS A001274:

Lal-Gillard and Firoozbakht ask whether there is another pair of consecutive integers in this sequence, apart from a(16) + 1 = a(17) = 5187, see link. - M. F. Hasler, Jan 05 2011

Up to 10^13 there are 10755 terms, and no further consecutive pairs like (5186, 5187). - Giovanni Resta, Feb 27 2014


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