A363172 Primitive terms of A363171: terms of A363171 with no proper divisor in A363171.

6, 10, 14, 44, 52, 105, 136, 152, 184, 232, 248, 286, 374, 418, 442, 495, 506, 592, 656, 688, 752, 848, 944, 976, 1292, 1564, 1748, 1755, 1972, 2108, 2144, 2145, 2204, 2272, 2336, 2356, 2516, 2528, 2656, 2668, 2788, 2805, 2812, 2848, 2852, 2924, 2925, 3104, 3116

Offset

1,1

Comments

If k is a term then m*k is a term of A363171 for all m >= 1.

The least odd term is a(6) = 105, and the least term that is coprime to 6 is a(34832) = 37182145.

Links

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

Mathematica

q[n_] := DivisorSigma[-1, n * Times @@ FactorInteger[n][[;; , 1]]] > 2; primQ[n_] := q[n] && AllTrue[Divisors[n], # == n || ! q[#] &]; Select[Range[3200], primQ]

Prog

(PARI) A064549(n) = { my(f=factor(n)); prod(i=1, #f~, f[i, 1]^(f[i, 2]+1)); };
isA363171(n) = sigma(A064549(n), -1) > 2;
is(n) = { if(!isA363171(n), return(0)); fordiv(n, d, if(d < n && isA363171(d), return(0))); return(1) };

Crossrefs

Cf. A363171.

Sequence in context: A259021 A171251 A074980 * A059218 A362600 A361606

Adjacent sequences: A363169 A363170 A363171 * A363173 A363174 A363175

Keyword

nonn

Author

Amiram Eldar, May 19 2023

Status

approved