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A359566
Primitive terms of A359565: terms of A359565 with no proper divisor in A359565.
4
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
1,1
COMMENTS
If k is a term then all the positive multiples of k are terms of A359565.
LINKS
MATHEMATICA
q[n_] := Max[Tally[EulerPhi[Divisors[n]]][[;; , 2]]] > 2; primQ[n_] := q[n] && AllTrue[Divisors[n], # == n || !q[#] &]; Select[Range[17000], primQ]
PROG
(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);
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Jan 06 2023
STATUS
approved