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A089200
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Primes p such that p-1 is divisible by a cube.
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6
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17, 41, 73, 89, 97, 109, 113, 137, 163, 193, 233, 241, 251, 257, 271, 281, 313, 337, 353, 379, 401, 409, 433, 449, 457, 487, 521, 541, 569, 577, 593, 601, 617, 641, 673, 751, 757, 761, 769, 809, 811, 857, 881, 919, 929, 937, 953, 977
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Prime[Range[200]], Count[Transpose[FactorInteger[#-1]][[2]], _?(#>2&)]>0&] (* Harvey P. Dale, Jan 01 2012 *)
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PROG
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(PARI) powerfreep3(n, p, k) = { c=0; pc=0; forprime(x=2, n, pc++; if(ispowerfree(x+k, p)==0, c++; print1(x", "); ) ); print(); print(c", "pc", "c/pc+.0) } ispowerfree(m, p1) = { flag=1; y=component(factor(m), 2); for(i=1, length(y), if(y[i] >= p1, flag=0; break); ); return(flag) }
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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