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The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.
3

%I #21 Dec 23 2024 14:53:42

%S 0,3,2,5,6,95,36,115,66,125,188,165,208,175,552,205,582,215,704,225,

%T 10076,425,10176,1135,10276,2145,10576,2245,11086,2745,11186,3155,

%U 11586,3865,11686,4375,11986,4575,12086,5385,12586,5595

%N The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.

%C 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.]

%C There are four possible solutions: see A181881-A181884.

%H V. J. Pohjola, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2010-November/006331.html">a(n)+a(n+1) = palindromic prime</a>, Posting to the Sequence Fans Mailing List, Nov 11 2010.

%t lst = {}; a = 0; c = 2; 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 *)

%t a[1] = 0; pp = Select[Prime[Range[3000]], PalindromeQ]; lp = Length[pp]-1;

%t aa = Table[a[n] + a[n+1], {n, lp}]; Array[a, lp] /. Solve[Thread[aa == Rest[pp]]][[1]] (* _Jean-François Alcover_, Feb 17 2018 *)

%Y Cf. A002385, A181881, A181882, A181884.

%K nonn,easy,base,changed

%O 1,2

%A _N. J. A. Sloane_, Nov 18 2010

%E More terms from _Nathaniel Johnston_, Nov 22 2010