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A230498 a(n) is the minimal odd odious k>1, such that k^i, i=2,...,n, all are evil, and a(n)=0, if there is no such k. 3

%I #18 Aug 03 2023 03:45:55

%S 13,21,21,47,265,607,883,883,883,883,10865,10865,58241,58241,58241,

%T 75781,367815,766165,2931371,5288671,5288671,14838843,14838843,

%U 14838843,33417397,737812313,2774333869,3513898753,3513898753,3513898753,14369883465,14369883465,22865025261

%N a(n) is the minimal odd odious k>1, such that k^i, i=2,...,n, all are evil, and a(n)=0, if there is no such k.

%C A conjugate sequence to A230495 and A230496.

%C Conjecture: For all n, a(n) > 0.

%H Amiram Eldar, <a href="/A230498/b230498.txt">Table of n, a(n) for n = 2..39</a>

%t evQ[n_] := EvenQ[DigitCount[n, 2, 1]]; evExp[n_] := Module[{e = 1, p = n^2}, If[! evQ[n], While[evQ[p], p *= n; e++]]; e]; seq[nmax_] := Module[{e, emax = 1, n = 3, s = {}}, Do[e = evExp[n]; If[e > emax, s = Join[s, ConstantArray[n, e - emax]]; emax = e], {n, 3, nmax, 2}]; s]; seq[11000] (* _Amiram Eldar_, Aug 03 2023 *)

%Y Cf. A000069, A001969, A230494, A230495, A230496, A230497.

%K nonn,base

%O 2,1

%A _Vladimir Shevelev_ and _Peter J. C. Moses_, Oct 21 2013

%E a(27)-a(34) from _Amiram Eldar_, Aug 03 2023

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Last modified April 24 18:17 EDT 2024. Contains 371962 sequences. (Running on oeis4.)