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A137836 Emirps using only and all of the prime digits 2,3,5,7. 2
3257, 3527, 7253, 7523, 32257, 32537, 35227, 35257, 35327, 72253, 72353, 73523, 75223, 75253, 322573, 327553, 332573, 355723, 375223, 375233, 725357, 753527, 3223357, 3223537, 3225737, 3235577, 3235777, 3237527, 3252377, 3253753 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Marius A. Burtea, Table of n, a(n) for n = 1..1601 (up to 10^9)

MAPLE

read transforms : isA006567 := proc(n) local nrev ; if isprime(n) then nrev := digrev(n) ; nrev <> n and isprime(nrev)) ; else false ; fi ; end: isA137836 := proc(n) local dgs ; if isA006567(n) then dgs := convert(convert(n, base, 10), set) ; if dgs minus {2, 3, 5, 7} <> {} then false ; elif nops(dgs) <> 4 then false ; else true ; fi ; else false ; fi ; end: for n from 1 to 1000000 do p := ithprime(n) ; if isA137836(p) then print(p) ; fi ; od: # R. J. Mathar, Feb 28 2008

MATHEMATICA

Take[With[{nn=2}, Union[FromDigits/@Select[Select[Flatten[Permutations/@ Flatten[ Table[Join[{2, 3, 5, 7}, Table[2, {i}], Table[3, {j}], Table[5, {k}], Table[7, {l}]], {i, 0, nn}, {j, 0, nn}, {k, 0, nn}, {l, 0, nn}], 3], 1], PrimeQ[ FromDigits[#]]&], PrimeQ[FromDigits[Reverse[#]]]&]]], 100] (* Harvey P. Dale, Nov 07 2012 *)

CROSSREFS

Subsequence of A128388.

Sequence in context: A183656 A043606 A135134 * A251919 A338071 A234653

Adjacent sequences: A137833 A137834 A137835 * A137837 A137838 A137839

KEYWORD

nonn,base

AUTHOR

Lekraj Beedassy, Feb 12 2008

EXTENSIONS

Corrected and extended by R. J. Mathar, Feb 28 2008

STATUS

approved

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Last modified January 27 12:05 EST 2023. Contains 359840 sequences. (Running on oeis4.)