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A259391
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).
3
10, 1761702690, 7226006660, 16453361570, 95748657190, 104217487100, 111058349320, 141665059420, 168759510430, 177313689280, 177313689330, 178209124090, 188343072120, 347296044930, 347296045010, 381449093790, 381449093840, 445151776780, 491570264380
OFFSET
1,1
COMMENTS
Terms computed by G. Resta, cf. link to Prime Puzzle 776.
LINKS
EXAMPLE
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.
The next value of 10 in A259567 occurs at index n = 1761702690 = a(2).
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Jul 19 2015
STATUS
approved