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A045941 Numbers m such that the factorizations of m..m+4 have the same number of primes (including multiplicities). 15

%I #21 Feb 11 2023 22:52:29

%S 602,2522,2523,4202,4921,4922,5034,5282,7730,12122,18241,18242,18571,

%T 19129,21931,23161,23305,25203,25553,25554,27290,27291,29233,30354,

%U 30793,32035,33843,34561,35124,35714,36001,36835,40313,40314,40394,42182,45265,52854

%N Numbers m such that the factorizations of m..m+4 have the same number of primes (including multiplicities).

%H Donovan Johnson, <a href="/A045941/b045941.txt">Table of n, a(n) for n = 1..10000</a>

%t f[n_]:=Plus@@Last/@FactorInteger[n];lst={};lst={};Do[If[f[n]==f[n+1]==f[n+2]==f[n+3]==f[n+4],AppendTo[lst,n]],{n,0,9!}];lst (* _Vladimir Joseph Stephan Orlovsky_, May 12 2010 *)

%t Flatten[Position[Partition[Table[PrimeOmega[n],{n,55000}],5,1],_?(Length[ Union[#]]==1&),{1},Heads->False]] (* _Harvey P. Dale_, Nov 29 2015 *)

%Y Numbers m through m+k have the same number of prime divisors (with multiplicity): A045920 (k=1), A045939 (k=2), A045940 (k=3), this sequence (k=4), A045942 (k=5), A123103 (k=6), A123201 (k=7), A358017 (k=8), A358018 (k=9), A358019 (k=10).

%K nonn

%O 1,1

%A _David W. Wilson_

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Last modified April 18 04:31 EDT 2024. Contains 371767 sequences. (Running on oeis4.)