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%I #12 Aug 03 2023 03:45:33
%S 5,23,71,85,89,163,225,225,225,225,6075,6075,9859,9859,9859,9859,9859,
%T 9859,5031037,10430265,11896187,11896187,11896187,22402429,340713205,
%U 570919625,570919625,570919625,1496195709,1496195709,1496195709,5743845611,8271306199,8271306199,8271306199
%N a(n), n>=2, is the minimal odd evil k, such that k^i, i=2,3,...,n, all are odious, 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.
%t odQ[n_] := OddQ[DigitCount[n, 2, 1]]; odExp[n_] := Module[{e = 1, p = n^2}, If[! odQ[n], While[odQ[p], p *= n; e++]]; e]; seq[nmax_] := Module[{e, emax = 1, n = 3, s = {}}, Do[e = odExp[n]; If[e > emax, s = Join[s, ConstantArray[n, e - emax]]; emax = e], {n, 3, nmax, 2}]; s]; seq[10000] (* _Amiram Eldar_, Aug 03 2023 *)
%Y Cf. A000069, A001969, A230454, A230495, A230496.
%K nonn,base
%O 2,1
%A _Vladimir Shevelev_ and _Peter J. C. Moses_, Oct 21 2013
%E a(26)-a(36) from _Amiram Eldar_, Aug 03 2023