A190384 Numbers with prime factorization pqrs^2t^4.

55440, 65520, 85680, 92400, 95760, 102960, 109200, 115920, 124740, 129360, 134640, 142800, 144144, 146160, 147420, 150480, 152880, 156240, 159120, 159600, 171600, 177840, 182160, 186480, 188496, 192780, 193200, 199920, 203280, 206640

Offset

1,1

Links

T. D. Noe, Table of n, a(n) for n = 1..1000

Will Nicholes, Prime Signatures

Mathematica

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 1, 2, 4}; Select[Range[300000], f]

Prog

(PARI) list(lim)=my(v=List(), t1, t2, t3, t4); forprime(p1=2, sqrtnint(lim\420, 4), t1=p1^4; forprime(p2=2, sqrtint(lim\(30*t1)), if(p2==p1, next); t2=p2^2*t1; forprime(p3=2, lim\(6*t2), if(p3==p1 || p3==p2, next); t3=p3*t2; forprime(p4=2, lim\(2*t3), if(p4==p1 || p4==p2 || p4==p3, next); t4=p4*t3; forprime(p5=2, lim\t4, if(p5==p1 || p5==p2 || p5==p3 || p5==p4, next); listput(v, t4*p5)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016

Crossrefs

Cf. A190382, A190383.

Sequence in context: A204776 A237485 A092008 * A217692 A061740 A184094

Adjacent sequences: A190381 A190382 A190383 * A190385 A190386 A190387

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, May 09 2011

Status

approved