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A136040 Classes of the phi iteration for which the smallest number is prime. 3


%S 1,2,3,4,5,6,7,8,9,10,14,16,17,19,21,22,25,26,29,31,41,49,51,52,55,58,

%T 59,60,63,65,66,67,69,71,74,77,79,81,82,87,89,108,109,113,114,116,119,

%U 122,124,127,129,130,136,137,142,143,145,147,148,151,154,158,159,161,162,163

%N Classes of the phi iteration for which the smallest number is prime.

%C Rows of A058812 which begin with a prime. The actual primes are in A092873, which is A007755(n+2) for the n in this sequence.

%H T. D. Noe, <a href="/A136040/b136040.txt">Table of n, a(n) for n=1..288</a>

%H T. D. Noe, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL11/Noe/noe080107.html">Primes in classes of the iterated totient function</a>, JIS 11 (2008) 08.1.2

%H Harold Shapiro, <a href="http://www.jstor.org/stable/2303988">An arithmetic function arising from the phi function</a>, Amer. Math. Monthly, Vol. 50, No. 1 (1943), 18-30.

%K nonn

%O 1,2

%A _T. D. Noe_, Dec 12 2007

%E Added 63 and 159. - _T. D. Noe_, Nov 18 2008

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Last modified August 3 22:03 EDT 2021. Contains 346441 sequences. (Running on oeis4.)