A066695 Numbers k such that Euler phi(k) / Carmichael lambda(k) = 12.

252, 273, 315, 364, 399, 468, 481, 532, 546, 630, 651, 665, 684, 693, 741, 756, 777, 793, 798, 855, 868, 903, 945, 949, 962, 988, 1001, 1036, 1071, 1085, 1116, 1204, 1209, 1261, 1281, 1287, 1302, 1330, 1332, 1386, 1395, 1404, 1407, 1417, 1449, 1463

Offset

1,1

Links

Table of n, a(n) for n=1..46.

Mathematica

Select[Range[2000], EulerPhi[#]/CarmichaelLambda[#] == 12 &] (* Alonso del Arte, Apr 17 2017 *)

Prog

(PARI) {cmf(f)=if( ((f[1]==2)&&(f[2]>2)), eulerphi(f[1]^f[2])/2, eulerphi(f[1]^f[2])) }
{cl(f)= k=factor(f); l=1; for(x=1, omega(f), l=lcm(l, cmf([k[x, 1], k[x, 2]]))); l }
{A0(n)=eulerphi(n)/cl(n)}
for(x=1, 10001, if(A0(x)==12, print1(x, ", ")))
(PARI) isok(k) = eulerphi(k)/lcm(znstar(k)[2]) == 12; \\ Michel Marcus, May 25 2022

Crossrefs

Cf. A000010, A002322.

Continuation of A062373, A062374, A062375, A062376, A062377.

Sequence in context: A045182 A330616 A046331 * A104396 A207373 A072443

Adjacent sequences: A066692 A066693 A066694 * A066696 A066697 A066698

Keyword

easy,nonn

Author

Randall L Rathbun, Jan 12 2002

Status

approved