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A062832
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Numbers k such that k and k+2 have the same number of divisors.
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10
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3, 5, 6, 8, 11, 17, 18, 29, 33, 40, 41, 50, 54, 55, 59, 71, 85, 91, 93, 101, 102, 107, 123, 128, 136, 137, 141, 143, 149, 152, 159, 179, 182, 183, 184, 185, 191, 197, 198, 201, 203, 213, 215, 217, 219, 227, 230, 235, 239, 242, 243, 246, 247, 248, 265, 269, 281
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OFFSET
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1,1
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COMMENTS
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The lesser member of every twin-prime pair occurs in this sequence. Hence A001359 is a subsequence. - T. D. Noe, Sep 17 2007
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LINKS
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MATHEMATICA
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Select[Range[300], DivisorSigma[0, #]==DivisorSigma[0, #+2]&] (* Harvey P. Dale, Mar 01 2012 *)
Position[Partition[DivisorSigma[0, Range[300]], 3, 1], _?(#[[1]]==#[[3]]&)]// Flatten//Quiet (* Harvey P. Dale, Mar 17 2017 *)
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PROG
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(PARI) je=[]; for(n=1, 1000, a=numdiv(n); b=numdiv(n+2); if(a==b, je=concat(je, n))); je
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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