A162571 Palindromes which are sums of two consecutive primes.

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

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