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 A261493 Palindromes that are concatenation of palindromic prime numbers in increasing order up to the n-th and then in decreasing order. 1
 2, 232, 23532, 2357532, 2357117532, 235711101117532, 235711101131101117532, 235711101131151131101117532, 235711101131151181151131101117532, 235711101131151181191181151131101117532, 235711101131151181191313191181151131101117532 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A043037. LINKS EXAMPLE For n=6, the first 6 palindromic primes are 2,3,5,7,11,101. Relevant subsequence that produce a(6) is 2,3,5,7,11,101,11,7,5,3,2. Concatenation of items with that order determines a(6) = 235711101117532. MATHEMATICA palQ[n_] := Reverse[idn = IntegerDigits@ n] == idn; s = Select[ Prime@ Range@ 1000, palQ]; f[n_] := FromDigits@ Flatten[ IntegerDigits@# & /@ Join[ Take[s, n], Reverse@ Take[s, n - 1]]]; Array[f, 11] (* Robert G. Wilson v, Aug 24 2015 *) CROSSREFS Cf. A002385, A048677. Sequence in context: A113800 A133495 A066622 * A012671 A012526 A012668 Adjacent sequences:  A261490 A261491 A261492 * A261494 A261495 A261496 KEYWORD nonn,easy,base AUTHOR Altug Alkan, Aug 21 2015 STATUS approved

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Last modified December 9 00:32 EST 2019. Contains 329871 sequences. (Running on oeis4.)