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A088149 Smallest prime which when rotated through all its binary places produces n primes, not counting any repeats. 1
2, 5, 11, 43, 167, 2143, 2423, 2687, 41903, 548543, 711679, 786431, 9010423, 10452461 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is probably not the case that this always produces the same bit cycle as A088148. - Franklin T. Adams-Watters, Mar 29 2014

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

a(5) = 167 because 167 in base two is 10100111. This will produce eight possible new numbers; 01001111 = 79, 10011110 = 158, 00111101 = 61, 01111010 = 122, 11110100 = 244, 11101001 = 233, 11010011 = 211 and back to the beginning 10100111 = 167. Of those eight numbers (79, 158, 61, 122, 244, 233, 211 & 167) only five of them are primes. Notice that this is the same bit cycle as in A088148 but rotated differently.

MATHEMATICA

f[n_] := Count[ PrimeQ[ Union[ Table[ FromDigits[ RotateLeft[ IntegerDigits[n, 2], i], 2], {i, 1, Floor[ Log[2, n] + 1]}]]], True]; NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; a = Table[0, {100}]; k = 2; Do[c = f[k]; If[c < 101 && a[[c]] == 0, a[[c]] = k]; k = NextPrim[k], {n, 1, 2750000}]; a

CROSSREFS

Cf. A088148.

Sequence in context: A172297 A128231 A088148 * A153989 A160859 A106887

Adjacent sequences:  A088146 A088147 A088148 * A088150 A088151 A088152

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 19 2003

EXTENSIONS

Edited by Franklin T. Adams-Watters, Mar 29 2014

STATUS

approved

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Last modified January 29 16:58 EST 2020. Contains 331347 sequences. (Running on oeis4.)