The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 4 19:07 EST 2022. Contains 358563 sequences. (Running on oeis4.)