A190385
Numbers with prime factorization pqrs^3t^3.
Original entry on oeis.org
83160, 98280, 128520, 143640, 154440, 173880, 201960, 216216, 219240, 225720, 231000, 234360, 238680, 266760, 273000, 273240, 279720, 282744, 309960, 316008, 322920, 325080, 334152, 344520, 348840, 355320, 357000, 368280, 373464, 382536
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,1,3,3};Select[Range[600000],f]
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list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtnint(lim\840, 3), t1=p^3; forprime(q=2,sqrtnint(lim\(30*t1), 3), if(q==p, next); t2=q^3*t1; forprime(r=2,lim\(6*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2,lim\(2*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2,lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
A190386
Numbers with prime factorization pqr^2s^2t^3.
Original entry on oeis.org
138600, 163800, 194040, 207900, 214200, 229320, 239400, 245700, 257400, 289800, 291060, 299880, 304920, 321300, 323400, 335160, 336600, 343980, 346500, 359100, 365400, 376200, 382200, 386100, 390600, 397800, 405720, 409500, 425880, 434700
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,2,2,3};Select[Range[600000],f]
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list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtnint(lim\1260, 3), t1=p^3; forprime(q=2,sqrtint(lim\(60*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(6*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,lim\(2*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2,lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
A190387
Numbers with prime factorization pq^2r^2s^2t^2.
Original entry on oeis.org
485100, 573300, 749700, 762300, 837900, 1014300, 1064700, 1067220, 1278900, 1367100, 1415700, 1490580, 1631700, 1673100, 1778700, 1808100, 1820700, 1851300, 1896300, 2069100, 2072700, 2274300, 2337300, 2484300, 2504700, 2548980, 2585700
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,2,2,2,2};Select[Range[4000000],f]
Take[(Times@@(#^{1,2,2,2,2}))&/@Flatten[Permutations[#]&/@Subsets[ Prime[ Range[ 20]],{5}],1]//Union,50] (* Harvey P. Dale, Jan 18 2020 *)
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list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtint(lim\6300), t1=p^2; forprime(q=2,sqrtint(lim\(180*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(12*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,sqrtint(lim\(2*t3)), if(s==p || s==q || s==r, next); t4=s^2*t3; forprime(t=2,lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
Showing 1-3 of 3 results.