A333020 Starts of runs of 3 consecutive even numbers that are all totient numbers (A002202).
2, 4, 6, 8, 16, 18, 20, 28, 40, 42, 44, 52, 54, 56, 78, 80, 100, 102, 104, 106, 108, 126, 128, 136, 160, 162, 164, 176, 196, 208, 220, 222, 224, 260, 268, 292, 328, 342, 344, 356, 378, 380, 416, 438, 440, 460, 462, 464, 476, 498, 500, 502, 504, 520, 560, 584
Offset: 1
Keywords
Examples
2 is a term since 2, 4 and 6 are all totient numbers.
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
- Wikipedia, Totient numbers.
Crossrefs
Programs
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PARI
m = 3; v = vector(m); for(k=1, m, v[k] = istotient(2*k)); for(k = m+1, 300, if(Set(v) == [1], print1(2*(k-m),", ")); v = concat(v[2..m], istotient(2*k)))