A079052 - OEIS

A079052

Recamán variation: a(1) = 1; for n > 1, a(n) = a(n-1)-f(n) if that number is positive and not already in the sequence, otherwise a(n) = a(n-1)+f(n), where f(n)=phi(n) (cf. A000010).

1, 2, 4, 6, 10, 8, 14, 18, 12, 16, 26, 22, 34, 28, 20, 28, 44, 38, 56, 48, 36, 46, 24, 32, 52, 40, 58, 70, 42, 50, 80, 64, 84, 68, 92, 104, 140, 122, 98, 82, 122, 110, 152, 132, 108, 86, 132, 116, 74, 54, 86, 62, 114, 96, 136, 112, 76, 104, 162, 146, 206, 176, 212, 180, 228