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A186086
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Beastly primes (version 1): either 666 followed by 0's and a 1 or 7 at the right end or a palindrome with 666 in the center, 0's surrounding these digits, and 1 or 7 at both ends.
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8
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6661, 16661, 66601, 76667, 700666007, 6660000000001, 666000000000001, 700000666000007, 70000006660000007, 6660000000000000000000000007, 66600000000000000000000000007, 1000000000000066600000000000001
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OFFSET
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1,1
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COMMENTS
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Differs from A131645 in that 26669, 46663, 56663, 66617, 66629, 66643, 66653, 66683, 66697, 96661, 96667, 106661, 106663, 106669, 116663, 146669, 166601, 166603, 166609, 166613, 166619, 166627, 166631, 166643, 166657, 166667, 166669, 166679, are not included here.
76667 is the largest beastly prime that does not contain the digit "0".
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LINKS
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MATHEMATICA
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e = 14; p = 666*10^n + 1; q = (10^(n + 2) + 666)*10^n + 1; Select[Union[Table[p, {n, 2*e}], Table[p + 6, {n, 2*e}], Table[q, {n, e}], Table[q + 6*10^(2*n + 2) + 6, {n, e}]], PrimeQ] (* Arkadiusz Wesolowski, Sep 21 2011 *)
Module[{nn=35, bp1, bp2, bp3, bp4}, bp1=FromDigits/@ Table[Join[PadRight[ {6, 6, 6}, n1, 0], {1}], {n1, 3, nn}]; bp2=FromDigits/@ Table[Join[ PadRight[ {6, 6, 6}, n2, 0], {7}], {n2, 3, nn}]; bp3=FromDigits/@ Table[Join[PadRight[ {1}, n3, 0], {6, 6, 6}, PadLeft[ {1}, n3, 0]], {n3, 1, nn/2}]; bp4=FromDigits/@ Table[Join[PadRight[{7}, n3, 0], {6, 6, 6}, PadLeft[ {7}, n3, 0]], {n3, 1, nn/2}]; Select[Sort[Join[bp1, bp2, bp3, bp4]], PrimeQ]] (* Harvey P. Dale, Jan 18 2017 *)
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CROSSREFS
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KEYWORD
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nonn,base,dumb
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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