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A237201
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Smallest integer m such that the n consecutive numbers m, m+1, ..., m+n-1 have n prime factors each, counted with multiplicity; a(n) = 0 if no such number exists.
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1
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Table[First@Select[Range[10^6], Union[PrimeOmega[(#+Range[n]-1)]]==={n}&, 1], {n, 5}] Wouter Meeussen, Feb 09 2014
With[{po=PrimeOmega[Range[633000]]}, Table[SequencePosition[po, PadRight[{}, n, n], 1][[1, 1]], {n, 5}]] (* Requires Mathematica version 10 or later *) (* The program generates the first 5 terms of the sequence. *) (* Harvey P. Dale, Jun 15 2021 *)
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PROG
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(Python)
import sympy
from sympy import isprime
from sympy import factorint
def PrimeFact(x):
..n = 9930000
..lst = []
..while n < 10**10:
....if not isprime(n):
......count = 0
......for i in range(n, n+x):
........if sum(factorint(i).values()) == x:
..........count += 1
........else:
..........n += 1
..........break
......if count == x:
........return n
....else:
......n += 1
(PARI) for(n=1, 5, for(k=2^n-1, oo, my(found=1); for(j=1, n, if(bigomega(k+j)!=n, found=0; break)); if(found, print1(k+1, ", "); break))) \ Hugo Pfoertner, Oct 21 2020
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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