A359566 Primitive terms of A359565: terms of A359565 with no proper divisor in A359565.

12, 40, 126, 364, 544, 546, 1026, 1100, 1170, 1650, 2812, 3591, 3608, 4095, 4100, 4214, 4218, 4510, 6138, 6150, 7564, 8658, 9394, 9548, 9990, 10804, 10850, 11096, 11132, 11346, 11368, 12078, 13286, 13870, 13950, 14210, 14322, 16206, 16376, 16698, 17082, 17290

Offset: 1

Author

Amiram Eldar, Jan 06 2023

Keywords

• nonn

Comments

If k is a term then all the positive multiples of k are terms of A359565.

Links

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

Crossrefs

Cf. A326835, A359563, A359564, A359565.

Programs

Mathematica

q[n_] := Max[Tally[EulerPhi[Divisors[n]]][[;; , 2]]] > 2; primQ[n_] := q[n] && AllTrue[Divisors[n], # == n || !q[#] &]; Select[Range[17000], primQ]

PARI

is1(k) = vecmax(matreduce(apply(x->eulerphi(x), divisors(k)))[,2]) > 2;
is(k) = fordiv(k, d, if(is1(d), return(d==k))); return(0);