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 A210734 Primes p such that p + 1 or p - 1 is a concatenation of successive even numbers starting from 2. 2
 3, 23, 2467, 246809, 246811, 24681012141619, 24681012141618202224262830323436384041, 24681012141618202224262830323436384042444649 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(9) has 625 digits, a(10) has 1476 digits, a(11) has 5048 digits, a(12) has 39024 digits. LINKS Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10 G. L. Honaker, Jr. and Chris Caldwell, 24681...50451 (625-digits) Henri & Renaud Lifchitz, PRP Records MATHEMATICA lst = {}; c = 0; Do[c = c*10^IntegerLength[n] + n; a = c - 1; If[PrimeQ[a], AppendTo[lst, a]]; b = c + 1; If[PrimeQ[b], AppendTo[lst, b]], {n, 2, 48, 2}]; lst CROSSREFS Cf. A019520. Sequence in context: A088056 A009593 A009818 * A166315 A113577 A224700 Adjacent sequences:  A210731 A210732 A210733 * A210735 A210736 A210737 KEYWORD base,nonn AUTHOR Arkadiusz Wesolowski, May 10 2012 STATUS approved

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Last modified February 20 20:55 EST 2019. Contains 320345 sequences. (Running on oeis4.)