A241198 Denominator of new minima of phi(p-1)/(p-1), where phi is Euler's totient function and p = prime(n).

1, 2, 3, 15, 35, 77, 1463, 1309, 1001, 4147, 2093, 19019, 17017, 39767, 35581, 323323, 10023013, 1339481, 676039, 20957209, 2800733, 86822723

Offset

1,2

Comments

The values of p are in A241196. The numerator is in A241197.

Links

Table of n, a(n) for n=1..22.

Mathematica

tMin = {{2, 1}}; Do[p = Prime[n]; tn = EulerPhi[p - 1]/(p - 1); If[tn < tMin[[-1, -1]], AppendTo[tMin, {p, tn}]], {n, 10^7}]; Denominator[Transpose[tMin][[2]]]

Crossrefs

Cf. A008330 (phi(prime(n)-1)), A073918, A241194, A241195.

Sequence in context: A244330 A342867 A060753 * A356094 A296296 A143880

Adjacent sequences: A241195 A241196 A241197 * A241199 A241200 A241201

Keyword

nonn,frac,more

Author

T. D. Noe, Apr 17 2014

Extensions

a(20)-a(22) from Giovanni Resta, Apr 14 2016

Status

approved