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A181881 The sums of pairs of adjacent terms are the odd palindromic primes in ascending order. 4
1, 2, 3, 4, 7, 94, 37, 114, 67, 124, 189, 164, 209, 174, 553, 204, 583, 214, 705, 224, 10077, 424, 10177, 1134, 10277, 2144, 10577, 2244, 11087, 2744, 11187, 3154, 11587, 3864, 11687, 4374, 11987, 4574, 12087, 5384, 12587, 5594, 12887, 6504, 13387 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This sequence was originally presented at http://www.sanaristikot.net by Jaakko Himberg (jaska.himberg(AT)suomiforum.com), Nov 06 2010. [Added by V.J. Pohjola, Nov 25 2010.]

There are four possible solutions: see A181881-A181884.

LINKS

V. J. Pohjola, Table of n, a(n) for n = 1..113

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

MATHEMATICA

lst = {}; a = 1; c = 1; 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 < 100000, Goto[alku1]]; lst (* V.J. Pohjola, Nov 22 2010 *)

a[1] = 1; 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, A181882, A181883, A181884.

Sequence in context: A158652 A127074 A109617 * A071373 A229597 A175060

Adjacent sequences:  A181878 A181879 A181880 * A181882 A181883 A181884

KEYWORD

nonn,easy,base

AUTHOR

N. J. A. Sloane, Nov 18 2010

EXTENSIONS

More terms from V.J. Pohjola, Nov 22 2010

STATUS

approved

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Last modified April 20 04:42 EDT 2019. Contains 322294 sequences. (Running on oeis4.)