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A090652
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Numbers all of whose prime factors end in 7.
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1
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7, 17, 37, 47, 49, 67, 97, 107, 119, 127, 137, 157, 167, 197, 227, 257, 259, 277, 289, 307, 317, 329, 337, 343, 347, 367, 397, 457, 467, 469, 487, 547, 557, 577, 587, 607, 617, 629, 647, 677, 679, 727, 749, 757, 787, 797, 799, 827, 833, 857, 877, 887, 889
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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[Range[1000], Union[Mod[Transpose[FactorInteger[#]][[1]], 10]]=={7}&] (* Harvey P. Dale, May 28 2014 *)
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PROG
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(PARI) numbers whose factors end in m endfactm(n, m) = { flag=0; for(x=2, n, y=factor(x); z=y[, 1]; ln=length(z); for(j=1, ln, if(z[j]%10<>m, flag=0; break, flag=1) ); if(flag==1, print1(x", ")) ) }
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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