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A181881
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The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.
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4
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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
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OFFSET
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1,2
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COMMENTS
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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.]
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LINKS
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MATHEMATICA
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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-François Alcover, Feb 17 2018 *)
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CROSSREFS
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KEYWORD
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nonn,easy,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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