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%I #28 Feb 11 2023 22:51:57
%S 602,603,1083,2012,2091,2522,2523,2524,2634,2763,3243,3355,4023,4202,
%T 4203,4921,4922,4923,5034,5035,5132,5203,5282,5283,5785,5882,5954,
%U 5972,6092,6212,6476,6962,6985,7314,7730,7731,7945,8393,8825,8956,8972,9162
%N Numbers m such that the factorizations of m..m+3 have the same number of primes (including multiplicities).
%H Zak Seidov and Michael De Vlieger, <a href="/A045940/b045940.txt">Table of n, a(n) for n = 1..11998</a> (First 3356 terms from Zak Seidov)
%t f[n_]:=Plus@@Last/@FactorInteger[n];lst={};lst={};Do[If[f[n]==f[n+1]==f[n+2]==f[n+3],AppendTo[lst,n]],{n,0,8!}];lst (* _Vladimir Joseph Stephan Orlovsky_, May 12 2010 *)
%t SequencePosition[PrimeOmega[Range[10000]],{x_,x_,x_,x_}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 02 2020 *)
%o (PARI) isok(n) = (bigomega(n) == bigomega(n+1)) && (bigomega(n+1) == bigomega(n+2)) && (bigomega(n+2) == bigomega(n+3)); \\ _Michel Marcus_, Jan 06 2015
%Y Numbers m through m+k have the same number of prime divisors (with multiplicity): A045920 (k=1), A045939 (k=2), this sequence (k=3), A045941 (k=4), A045942 (k=5), A123103 (k=6), A123201 (k=7), A358017 (k=8), A358018 (k=9), A358019 (k=10).
%Y Cf. A045932 (similar, with omega).
%K nonn
%O 1,1
%A _David W. Wilson_
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