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A246497
Smallest k such that 9^^n is not congruent to 9^^(n-1) mod k, where 9^^n denotes the power tower 9^9^...^9 (in which 9 appears n times).
7
3, 7, 23, 47, 283, 719, 1439, 2879, 34549, 138197, 1266767, 14619833, 36449279, 377982107, 1432349099
OFFSET
1,1
COMMENTS
For general remarks regarding sequences of this type, see A246491.
This particular sequence shares all known terms with A082449. they might be identical.
PROG
(Sage, cython) Use linked source from A246491 with this command: find_k_values(9, 1, 1)
KEYWORD
nonn,more
AUTHOR
STATUS
approved