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 A179696 Numbers with prime signature {7,1,1}, i.e., of form p^7*q*r with p, q and r prime. 6
 1920, 2688, 4224, 4480, 4992, 6528, 7040, 7296, 8320, 8832, 9856, 10880, 11136, 11648, 11904, 12160, 14208, 14720, 15232, 15744, 16512, 17024, 18048, 18304, 18560, 19840, 20352, 20608, 21870, 22656, 23424, 23680, 23936, 25728, 25984, 26240, 26752, 27264 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 Will Nicholes Prime Signatures OEIS Wiki, Numbers with same prime signature. MAPLE a:= proc(n) option remember; local k;       for k from 1+ `if` (n=1, 1, a(n-1))         while sort (map (x-> x[2], ifactors(k)[2]), `>`)<>[7, 1, 1]       do od; k     end: seq (a(n), n=1..40); # Alois P. Heinz, Jan 23 2011 MATHEMATICA f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 7}; Select[Range[30000], f] PROG (PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\6)^(1/7), t1=p^7; forprime(q=2, lim\t1, if(p==q, next); t2=t1*q; forprime(r=q+1, lim\t2, if(p==r, next); listput(v, t2*r)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011 CROSSREFS Cf. A006881, A007304, A065036, A085986, A085987, A092759, A178739, A179642, A179643, A179644, A179645, A179646, A179664, A179665, A179666, A179667, A179668, A179669, A179670, A179671, A179672, A179688, A179689, A179690, A179691, A179692, A179693, A179694, A179695. Sequence in context: A222928 A309031 A077087 * A249840 A061374 A282474 Adjacent sequences:  A179693 A179694 A179695 * A179697 A179698 A179699 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Jul 24 2010 EXTENSIONS Title edited by Daniel Forgues, Jan 22 2011 STATUS approved

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Last modified October 18 14:52 EDT 2019. Contains 328161 sequences. (Running on oeis4.)