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

602, 2522, 2523, 4202, 4921, 4922, 5034, 5282, 7730, 12122, 18241, 18242, 18571, 19129, 21931, 23161, 23305, 25203, 25553, 25554, 27290, 27291, 29233, 30354, 30793, 32035, 33843, 34561, 35124, 35714, 36001, 36835, 40313, 40314, 40394, 42182, 45265, 52854

Offset

1,1

Links

Donovan Johnson, Table of n, a(n) for n = 1..10000

Mathematica

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

Crossrefs

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).

Sequence in context: A124057 A252435 A363830 * A268588 A251462 A356893

Adjacent sequences: A045938 A045939 A045940 * A045942 A045943 A045944

Keyword

nonn

Author

David W. Wilson

Status

approved