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A088148 Least number which when rotated through all its binary places produces n primes, not counting any repeats. 1

%I

%S 2,5,11,43,158,2143,2302,2558,36542,548543,711679,786431,9010423,

%T 10452461

%N Least number which when rotated through all its binary places produces n primes, not counting any repeats.

%C It is probably not the case that this always produces the same bit cycle as A088149. - _Franklin T. Adams-Watters_, Mar 29 2014

%e a(5) = 158 because 158 in base two is 10011110. This will produce eight possible new numbers; 00111101 = 61, 01111010 = 122, 11110100 = 244, 11101001 = 233, 11010011 = 211, 10100111 = 167, 01001111 = 79 and back to the beginning 10011110 = 158. Of those eight numbers (61, 122, 244, 233, 211, 167, 79 & 158) only five of them are primes. Notice that this is the same bit cycle as in A088149 but rotated differently.

%t f[n_] := Count[ PrimeQ[ Union[ Table[ FromDigits[ RotateLeft[ IntegerDigits[n, 2], i], 2], {i, 1, Floor[ Log[2, n] + 1]}]]], True]; a = Table[0, {15}]; k = 1; Do[c = f[k]; If[c < 100 && a[[c+1]] == 0, a[[c+1]] = n]; k++, {n, 1, 10^7}]; a

%Y Cf. A088149.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Sep 19 2003

%E Edited by _Franklin T. Adams-Watters_, Mar 29 2014

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Last modified February 22 08:42 EST 2020. Contains 332133 sequences. (Running on oeis4.)