OFFSET
1,1
COMMENTS
What is a good way in the OEIS to show other such pairs of bases analogous to this?
EXAMPLE
a(1) = 73 because 73 (base 8) = 111 (which is a palindrome), and R(73) = 37 which is a different prime (base 10). a(2) = 97 because 97 (base 8) = 141 (which is a palindrome), and R(97) = 79 which is a different prime (base 10). a(3) = 113 because 113 (base 8) = 161 (which is a palindrome), and R(113) = 311 which is a different prime (base 10). a(4) = 12547 because 12547 (base 8) = 30403 (which is a palindrome), and R(12547) = 74521 which is a different prime (base 10).
MAPLE
isA006567 := proc(p) local r; if isprime(p) then r := digrev(p) ; r <> p and isprime(r) ; else false; end if; end proc: isA029803 := proc(n) local dgs, d; dgs := convert(n, base, 8) ; for d from 1 to nops(dgs)/2 do if op(d, dgs) <> op(-d, dgs) then return false; end if; end do ; return true; end proc: isA029976 := proc(n) isprime(n) and isA029803(n) ; end proc: isA168110 := proc(p) isA029976(p) and isA006567(p) ; end proc: A168110 := proc(n) option remember ; local a; if n = 1 then 73 ; else a := nextprime(procname(n-1)) ; while not isA168110(a) do a := nextprime(a) ; end do ; return a; end if; end proc: seq(A168110(n), n=1..30) ; # R. J. Mathar, Dec 06 2009
MATHEMATICA
okQ[n_]:=Module[{fridn=FromDigits[Reverse[IntegerDigits[n]]], idn8= IntegerDigits[n, 8]}, fridn!=n&&PrimeQ[fridn]&&idn8==Reverse[idn8]]; Select[Prime[Range[75000]], okQ] (* Harvey P. Dale, Aug 10 2011 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Jonathan Vos Post, Nov 18 2009
EXTENSIONS
Terms beyond a(10) by R. J. Mathar, Dec 06 2009
STATUS
approved