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A333019
Numbers k such that both k and k + 2 are totient numbers (A002202).
6
2, 4, 6, 8, 10, 16, 18, 20, 22, 28, 30, 40, 42, 44, 46, 52, 54, 56, 58, 64, 70, 78, 80, 82, 100, 102, 104, 106, 108, 110, 126, 128, 130, 136, 138, 148, 160, 162, 164, 166, 176, 178, 190, 196, 198, 208, 210, 220, 222, 224, 226, 238, 250, 260, 262, 268, 270, 280
OFFSET
1,1
LINKS
EXAMPLE
2 is a term since both 2 and 4 are totient numbers.
PROG
(PARI) for(k = 1, 150, if(istotient(2*k) && istotient(2*k+2), print1(2*k, ", ")))
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 05 2020
STATUS
approved