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%I #14 Apr 26 2019 08:03:11
%S 2,3,7,47,31,191,127,1021,3583,4093,6143,16381,8191,81919,262139,
%T 1114111,131071,786431,524287,4194301,14680063,16777213,67108859,
%U 654311423,671088637,738197503,536870909,5368709117,3758096383,34359738337,2147483647,21474836479
%N Smallest prime with exactly n consecutive ones in the longest run of ones in its binary expansion.
%H Chai Wah Wu, <a href="/A090593/b090593.txt">Table of n, a(n) for n = 1..3310</a>
%e a(1) = 2 since 2_d = 10_b. a(2) = 3 since 3_d = 11_b. a(3) = 7 since 7_d = 111_b. a(4) = 47 since 47_d = 101111_b.
%t a = Table[0, {30}]; NextPrim[n_] := Block[{k = n + 1}, While[ ! PrimeQ[k], k++ ]; k]; p = 2; Do[ m = Length[ Union[ DeleteCases[ Split[ IntegerDigits[p, 2]], 0, 2]][[ -1]]]; If[ a[[m]] == 0, a[[m]] = p]; p = NextPrim[p], {n, 1, 117000000}]
%Y Cf. A090000, A090587.
%K nonn,base
%O 1,1
%A _Robert G. Wilson v_, Dec 03 2003
%E a(28)-a(32) from _Donovan Johnson_, Sep 10 2013
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