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A129254 Numbers n such that both n and n+1 have at least one divisor of the form p^e with p<=e, p prime. 1

%I

%S 27,80,135,188,243,296,351,404,459,512,567,620,675,728,783,836,891,

%T 944,999,1052,1107,1160,1215,1268,1323,1376,1431,1484,1539,1592,1647,

%U 1700,1755,1808,1863,1916,1971,2024,2079,2132,2187,2240,2295,2348,2403,2456

%N Numbers n such that both n and n+1 have at least one divisor of the form p^e with p<=e, p prime.

%C A129251(a(n)) > 0, A129251(a(n)+1) > 0;

%C if A100716(k) = a(n) then: A100716(k+1) = a(n) + 1; subsequence of A100716.

%e 135=5*3^3 and 135+1=136=17*2^3, therefore 135 is a term: a(3)=135;

%e 188=47*2^2 and 188+1=189=7*3^3, therefore 188 is a term: a(4)=188.

%t SequencePosition[Table[If[AnyTrue[FactorInteger[n],#[[2]]>=#[[1]]&],1,0],{n,2500}],{1,1}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Sep 14 2019 *)

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Apr 07 2007

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Last modified November 11 22:31 EST 2019. Contains 329046 sequences. (Running on oeis4.)