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A123103 Numbers n such that factorizations of n..n+6 have same number of primes (including multiplicities). 4
211673, 298433, 355923, 381353, 460801, 506521, 540292, 568729, 690593, 705953, 737633, 741305, 921529, 1056529, 1088521, 1105553, 1141985, 1187121, 1362313, 1721522, 1811704, 1828070, 2016721, 2270633, 2369809, 2535721, 2590985 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subset of A045940 Numbers n such that factorizations of n..n+3 have same number of primes (including multiplicities).

LINKS

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

EXAMPLE

211673 = 7*11*2749, 211674 = 2*3*35279, 211675 = 5^2*8467, 211676 = 2^2*52919, 211677 = 3*37*1907, 211677 = 2*109*971, 211679 = 13*19*857 all 3-almost primes.

355923 = 3^2*71*557, 355924 = 2^2*101*881, 355925 = 5^2*23*619, 355926 = 2*3*137*433, 355927 = 11*13*19*131, 355928 = 2^3*44491, 355929 = 3*7*17*997 all 4-almost primes.

PROG

(PARI) c=0; p1=0; for(n=2, 10^8, p2=bigomega(n); if(p1==p2, c++; if(c>=6, print1(n-6 ", ")), c=0; p1=p2)) /* Donovan Johnson, Mar 20 2013 */

CROSSREFS

Cf. A045940, A045941, A045942, A123201.

Sequence in context: A340158 A097021 A236086 * A259756 A251511 A252880

Adjacent sequences:  A123100 A123101 A123102 * A123104 A123105 A123106

KEYWORD

nonn

AUTHOR

Zak Seidov, Nov 05 2006

EXTENSIONS

a(14)-a(27) from Donovan Johnson, Mar 26 2010

STATUS

approved

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Last modified May 14 13:50 EDT 2021. Contains 343884 sequences. (Running on oeis4.)