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A342062 a(n) is the number of divisors of prime(n)^8 - 1.

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%I A342062 #20 Mar 04 2021 01:43:03
%S A342062 8,24,48,84,96,192,192,288,224,192,576,576,672,2304,1024,768,768,192,
%T A342062 768,336,672,1024,3072,1344,864,576,448,1152,1536,512,2112,768,1792,
%U A342062 768,1152,1344,2304,960,896,1536,1728,1152,2560,1280,1728,504,1536,2304,1536
%N A342062 a(n) is the number of divisors of prime(n)^8 - 1.
%C A342062 a(n) >= 384 for n > 20.
%H A342062 Robert Israel, <a href="/A342062/b342062.txt">Table of n, a(n) for n = 1..10000</a>
%F A342062 a(n) = A000005(A000040(n)^8 - 1).
%e A342062    n  prime(n)      factorization of prime(n)^8 - 1      a(n)
%e A342062   --  --------  ---------------------------------------  ----
%e A342062    1      2           3   * 5   * 17                        8
%e A342062    2      3     2^5       * 5   * 41                       24
%e A342062    3      5     2^5 * 3         * 13 * 313                 48
%e A342062    4      7     2^6 * 3   * 5^2 * 1201                     84
%e A342062    5     11     2^5 * 3   * 5   * 61 * 7321                96
%e A342062    6     13     2^5 * 3   * 5   * 7 * 17 * 14281          192
%e A342062    7     17     2^7 * 3^2 * 5   * 29 * 41761              192
%e A342062    8     19     2^5 * 3^2 * 5   * 17 * 181 * 3833         288
%e A342062    9     23     2^6 * 3   * 5   * 11 * 53 * 139921        224
%e A342062   10     29     2^5 * 3   * 5   * 7 * 421 * 353641        192
%e A342062   11     31     2^8 * 3   * 5   * 13 * 37 * 409 * 1129    576
%e A342062   12     37     2^5 * 3^2 * 5   * 19 * 89 * 137 * 10529   576
%e A342062   13     41     2^6 * 3   * 5   * 7 * 29^2 * 137 * 10313  672
%e A342062   ...
%e A342062   20     71     2^6 * 3^2 * 5   * 7 * 2521 * 12705841     336
%p A342062 f:= n -> numtheory:-tau(ithprime(n)^8-1):
%p A342062 map(f, [$1..100]); # _Robert Israel_, Feb 28 2021
%t A342062 a[n_] := DivisorSigma[0, Prime[n]^8 - 1]; Array[a, 50] (* _Amiram Eldar_, Feb 27 2021 *)
%o A342062 (PARI) a(n) = numdiv(prime(n)^8-1); \\ _Michel Marcus_, Feb 27 2021
%Y A342062 Cf. A000005, A000040, A309906, A342063, A342064.
%K A342062 nonn
%O A342062 1,1
%A A342062 _Jon E. Schoenfield_, Feb 27 2021