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A181882 The sums of pairs of adjacent terms are the odd palindromic primes in ascending order. 3
2, 1, 4, 3, 8, 93, 38, 113, 68, 123, 190, 163, 210, 173, 554, 203, 584, 213, 706, 223, 10078, 423, 10178, 1133, 10278, 2143, 10578, 2243, 11088, 2743, 11188, 3153, 11588, 3863, 11688, 4373, 11988, 4573, 12088, 5383, 12588, 5593 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence was originally presented at http://www.sanaristikot.net by V.J. Pohjola, Nov 11 2010. [Added by V.J. Pohjola, Nov 25 2010.]

There are four possible solutions: see A181881-A181884.

LINKS

Table of n, a(n) for n=1..42.

V. J. Pohjola, a(n)+a(n+1) = palindromic prime, Posting to the Sequence Fans Mailing List, Nov 11 2010.

MATHEMATICA

lst = {}; a = 2; c = 0; Label[alku1]; b = c; Label[alku2]; b =b + 1; If[PrimeQ[a + b] && IntegerDigits[a + b] == Reverse[IntegerDigits[a + b]], AppendTo[lst, a], Goto[alku2]]; c = a; a = b; If[a < nn, Goto[alku1]]; lst  (* V.J. Pohjola, Nov 25 2010 *)

a[1] = 2; pp = Select[Prime[Range[3000]], PalindromeQ]; lp = Length[pp]-1;

aa = Table[a[n] + a[n+1], {n, lp}]; Array[a, lp] /. Solve[Thread[aa == Rest[pp]]][[1]] (* Jean-Fran├žois Alcover, Feb 17 2018 *)

CROSSREFS

Cf. A002385, A181881, A181883, A181884.

Sequence in context: A238757 A262230 A262155 * A109195 A258310 A217927

Adjacent sequences:  A181879 A181880 A181881 * A181883 A181884 A181885

KEYWORD

nonn,easy,base

AUTHOR

N. J. A. Sloane, Nov 18 2010

EXTENSIONS

More terms from Nathaniel Johnston, Nov 22 2010

STATUS

approved

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Last modified October 20 23:39 EDT 2018. Contains 316405 sequences. (Running on oeis4.)