A217142 Least number m such that phi(m) = phi(m+6n) and m is not divisible by n.

143, 52, 101, 124, 104, 123, 183, 156, 248, 144, 208, 267, 241, 365, 219, 248, 312, 306, 496, 369, 288, 432, 241, 543, 369, 468, 482, 386, 730, 444, 438, 432, 496, 1220, 624, 779, 612, 801, 915, 744, 723, 582, 576, 1095, 864, 488, 482, 641, 1086, 674, 738

Offset: 2

Author

Michel Marcus, Sep 27 2012

Keywords

• nonn

Links

• Donovan Johnson, Table of n, a(n) for n = 2..1000

Crossrefs

Cf. A000010, A179188, A217068, A217139, A217141.

Programs

PARI

fpr(Nmax, lim) = {for (i=2, Nmax,N = i*6;op = vector(N);f = 0;for (n=1, lim, if (op[n%N+1]+0==op[n%N+1]=eulerphi(n), if ((n-N) % i != 0, f = n-N;break;);););print1(f, ", "););}