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 A114996 a(n) = smallest palindrome > a(n-1) (for n > 0) such that the sum of its prime digits is equal to palindrome with index n, or -1 if none exists. 0
 0, -1, 2, 3, 22, 151, 222, 232, 323, 333, 353, 37273, 77577, 7772777, 377777773, 5777777775, 77777777777, 27777777777772, 577777757777775, 577777777777775, 37777777777777773, 2777777775777777772, 7777777775777777777 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Palindrome with index n is A002113(n). LINKS EXAMPLE a(0) = 0 since A002113(0) = 0 and the prime digits of 0 sum to 0. a(1) = -1 since A002113(1) = 1 and there is no number (all the more no palindrome) whose prime digits sum to 1. a(5) = 151 since A002113(5) = 5 and 151 is the smallest palindrome > a(4) = 22 whose prime digits sum to 5. CROSSREFS Cf. A002113. Sequence in context: A154254 A264696 A166122 * A153256 A137077 A046965 Adjacent sequences:  A114993 A114994 A114995 * A114997 A114998 A114999 KEYWORD base,sign AUTHOR Giovanni Teofilatto, Feb 23 2006 EXTENSIONS Edited, corrected and extended by Klaus Brockhaus, Mar 13 2006 a(16) and a(19) corrected, a(21) and a(22) added by Klaus Brockhaus, May 23 2007 STATUS approved

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Last modified May 31 13:01 EDT 2020. Contains 334748 sequences. (Running on oeis4.)