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Greatest exponent in prime-power factorization of prime(n)+3.
1

%I #11 Sep 09 2024 02:40:43

%S 1,1,3,1,1,4,2,1,1,5,1,3,2,1,2,3,1,6,1,1,2,1,1,2,2,3,1,1,4,2,1,1,2,1,

%T 3,1,5,1,1,4,1,3,1,2,3,1,1,1,1,3,2,2,2,1,2,1,4,1,3,2,1,3,1,1,2,6,1,2,

%U 2,5,2,1,1,3,1,1,3,4,2,2,1,3,1,2,1,1,2,2,4,1,1,1,2,1,1,1,9,2,1

%N Greatest exponent in prime-power factorization of prime(n)+3.

%H Robert Israel, <a href="/A023577/b023577.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A051903(3+A000040(n)). - _Robert Israel_, Mar 18 2019

%p f:= proc(n) max(map(t -> t[2], ifactors(ithprime(n)+3)[2])) end proc:

%p map(f, [$1..100]); # _Robert Israel_, Mar 18 2019

%t a[n_] := Max[FactorInteger[Prime[n] + 3][[;;, 2]]]; Array[a, 100] (* _Amiram Eldar_, Sep 09 2024 *)

%o (PARI) a(n) = vecmax(factor(prime(n) + 3)[,2]); \\ _Amiram Eldar_, Sep 09 2024

%Y Cf. A000040, A051903.

%K nonn

%O 1,3

%A _Clark Kimberling_