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%I #9 Mar 06 2020 00:57:17
%S 2,4,16,40,52,100,102,104,160,220,460,498,500,856,880,1276,1480,1660,
%T 1804,2200,2236,3016,3160,3460,4516,4780,5500,5920,6040,6196,6820,
%U 7240,7636,7696,7720,8536,8620,9196,9460,9880,10456,12916,13756,13960,14416,15640
%N Starts of runs of 5 consecutive even numbers that are all totient numbers (A002202).
%H Amiram Eldar, <a href="/A333022/b333022.txt">Table of n, a(n) for n = 1..10000</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Euler%27s_totient_function#Totient_numbers">Totient numbers</a>.
%e 2 is a term since 2, 4, 6, 8 and 10 are all totient numbers.
%o (PARI) m = 5; v = vector(m); for(k=1, m, v[k] = istotient(2*k)); for(k = m+1, 7500, if(Set(v) == [1], print1(2*(k-m),", ")); v = concat(v[2..m], istotient(2*k)))
%Y Cf. A000010, A002202, A005277, A063512, A083533, A333019, A333020, A333021, A333023, A333024.
%K nonn
%O 1,1
%A _Amiram Eldar_, Mar 05 2020
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