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A030994
9-automorphic numbers ending in 4: final digits of 9*n^2 agree with n.
1
4, 64, 264, 3264, 23264, 123264, 4123264, 54123264, 754123264, 5754123264, 75754123264, 675754123264, 6675754123264, 26675754123264, 526675754123264, 1526675754123264, 71526675754123264
OFFSET
1,1
COMMENTS
a(n) is the unique positive integer less than 10^n such that a(n) is divisible by 2^n and 9*a(n) - 1 is divisible by 5^n. - Eric M. Schmidt, Aug 18 2012
PROG
(Sage) [crt(0, inverse_mod(9, 5^n), 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012
CROSSREFS
Sequence in context: A062271 A110258 A056982 * A299147 A141046 A264055
KEYWORD
nonn,base
STATUS
approved