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Numbers n such that A258881(n+k) is prime for k=0,...,9; where A258881(x) = x + sum of the square of the digits of x (A003132).
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%I #36 Jul 20 2015 20:22:08

%S 10,1761702690,7226006660,16453361570,95748657190,104217487100,

%T 111058349320,141665059420,168759510430,177313689280,177313689330,

%U 178209124090,188343072120,347296044930,347296045010,381449093790,381449093840,445151776780,491570264380

%N Numbers n such that A258881(n+k) is prime for k=0,...,9; where A258881(x) = x + sum of the square of the digits of x (A003132).

%C Terms computed by G. Resta, cf. link to Prime Puzzle 776.

%H C. Riviera, <a href="http://www.primepuzzles.net/puzzles/puzz_776.htm">Puzzle 776. Ten consecutive integers such that...</a>, PrimePuzzles.net, March 2015.

%e For n = 10, A258881(10) = 10 + 1^2 + 0^2 = 11, A258881(11) = 11 + 1^2 + 1^2 = 13, A258881(12) = 12 + 1^2 + 2^2 = 17, ..., A258881(19) = 19 + 1^2 + 9^2 = 101 are all prime, therefore a(1) = 10.

%e The next value of 10 in A259567 occurs at index n = 1761702690 = a(2).

%Y Cf. A003132, A258881, A259567.

%K nonn,base

%O 1,1

%A _M. F. Hasler_, Jul 19 2015