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 A237201 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. 0
 2, 9, 170, 4023, 632148, 4843161124, 1981162639374 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA Table[First@Select[Range[10^6], Union[PrimeOmega[(#+Range[n]-1)]]==={n}&, 1], {n, 5}] Wouter Meeussen, Feb 09 2014 PROG (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 CROSSREFS Cf. A001222. Sequence in context: A182948 A081459 A038843 * A053294 A199695 A078524 Adjacent sequences:  A237198 A237199 A237200 * A237202 A237203 A237204 KEYWORD nonn,more,hard AUTHOR Derek Orr, Feb 04 2014 EXTENSIONS a(6) from Giovanni Resta, Feb 09 2014 a(7) from Giovanni Resta, Feb 10 2014 STATUS approved

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Last modified February 27 01:52 EST 2020. Contains 332299 sequences. (Running on oeis4.)