A190391
Numbers with prime factorization pqrs^2t^2u^2.
Original entry on oeis.org
900900, 1178100, 1261260, 1316700, 1392300, 1556100, 1593900, 1649340, 1843380, 1883700, 1949220, 1981980, 2009700, 2034900, 2102100, 2148300, 2178540, 2187900, 2231460, 2342340, 2375100, 2445300, 2463300, 2538900, 2564100, 2591820
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,1,2,2,2};Select[Range[3500000],f]
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list(lim)=my(v=List(),t1,t2,t3,t4,t5); forprime(p=2,sqrtint(lim\13860), t1=p^2; forprime(q=2,sqrtint(lim\(420*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(30*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,lim\(6*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2,lim\(2*t4), if(t==p || t==q || t==r || t==s, next); t5=t*t4; forprime(u=2,lim\t5, if(u==p || u==q || u==r || u==s || u==t, next); listput(v, t5*u))))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
A190316
Numbers with prime factorization pqrstuv^3.
Original entry on oeis.org
2042040, 2282280, 2762760, 2984520, 3483480, 3527160, 3612840, 3723720, 4037880, 4269720, 4444440, 4555320, 4594590, 4772040, 4869480, 4924920, 5091240, 5135130, 5165160, 5383560, 5442360, 5542680, 5645640, 5754840, 5811960, 6016920, 6163080, 6216210
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,1,1,1,1,3}; Select[Range[3000000],f]
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isA190316(n)=vecsort(factor(n)[,2])==[1, 1, 1, 1, 1, 1, 3]~ \\ Charles R Greathouse IV, May 10 2011
A190462
Numbers with prime factorization pqrstu^2v^2.
Original entry on oeis.org
3063060, 3423420, 4144140, 4476780, 5105100, 5225220, 5290740, 5419260, 5585580, 5705700, 6056820, 6404580, 6666660, 6832980, 6906900, 7147140, 7158060, 7304220, 7387380, 7461300, 7636860, 7657650, 7747740, 7987980, 8075340, 8163540, 8314020, 8468460
Offset: 1
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,1,1,1,2,2}; Select[Range[6000000],f]
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list(lim)=my(v=List(),t1,t2,t3,t4,t5,t6); forprime(p1=2,sqrtint(lim\60060), t1=p1^2; forprime(p2=2,sqrtint(lim\(2310*t1)), if(p2==p1, next); t2=p2^2*t1; forprime(p3=2,lim\(210*t2), if(p3==p1 || p3==p2, next); t3=p3*t2; forprime(p4=2,lim\(30*t3), if(p4==p1 || p4==p2 || p4==p3, next); t4=p4*t3; forprime(p5=2,lim\(6*t4), if(p5==p1 || p5==p2 || p5==p3 || p5==p4, next); t5=p5*t4; forprime(p6=2,lim\(2*t5), if(p6==p1 || p6==p2 || p6==p3 || p6==p4 || p6==p5, next); t6=p6*t5; forprime(p7=2,lim\t6, if(p7==p1 || p7==p2 || p7==p3 || p7==p4 || p7==p5 || p7==p6, next); listput(v, t6*p7)))))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
Showing 1-3 of 3 results.