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A162571 Palindromes which are sums of two consecutive primes. 2
5, 8, 222, 434, 696, 828, 2112, 2992, 4224, 4554, 6336, 8448, 8888, 20202, 21712, 21812, 22722, 23832, 25652, 25952, 26862, 27672, 29092, 29292, 41114, 42024, 42724, 43334, 43734, 44544, 47174, 47974, 60106, 61116, 62526, 62626, 63936, 64146, 64446, 64946 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale and Chai Wah Wu, Table of n, a(n) for n = 1..10000, first 1500 term from Harvey P. Dale.

FORMULA

A001043 INTERSECT A002113.

EXAMPLE

a(3) = 222= A002113(32) = A001043(29). a(4) = 434= A002113(53) = A001043(47).

MAPLE

isA002113 := proc(n) dgs := convert(n, base, 10) ; for i from 1 to nops(dgs)/2 do if op(i, dgs) <> op(-i, dgs) then RETURN(false); end if; end do: true; end proc:

A001043 := proc(n) ithprime(n)+ithprime(n+1) ; end proc:

for n from 1 do ps := A001043(n) ; if isA002113(ps) then printf("%d, \n", ps) ; fi; end do: # R. J. Mathar, Aug 14 2009

MATHEMATICA

palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; Select[Total/@ Partition[Prime[Range[5000]], 2, 1], palQ] (* Harvey P. Dale, Dec 30 2013 *)

CROSSREFS

Sequence in context: A267003 A151827 A258044 * A046490 A155214 A028934

Adjacent sequences:  A162568 A162569 A162570 * A162572 A162573 A162574

KEYWORD

nonn,base

AUTHOR

Claudio Meller, Jul 06 2009

EXTENSIONS

Keyword:base added by R. J. Mathar, Aug 14 2009

STATUS

approved

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Last modified April 20 09:59 EDT 2019. Contains 322309 sequences. (Running on oeis4.)