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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
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
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-François Alcover, Feb 17 2018 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
N. J. A. Sloane, Nov 18 2010
EXTENSIONS
More terms from Nathaniel Johnston, Nov 22 2010
STATUS
approved