A333019 Numbers k such that both k and k + 2 are totient numbers (A002202).

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

Author

Amiram Eldar, Mar 05 2020

Keywords

• nonn

Examples

			2 is a term since both 2 and 4 are totient numbers.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Wikipedia, Totient numbers.

Crossrefs

Cf. A000010, A002202, A005277, A063512, A083533, A333020, A333021, A333022, A333023, A333024.

Programs

PARI

for(k = 1, 150, if(istotient(2*k) && istotient(2*k+2), print1(2*k,", ")))