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 A030984 2-automorphic numbers: final digits of 2*n^2 agree with n. 1
 8, 88, 688, 4688, 54688, 554688, 3554688, 93554688, 893554688, 893554688, 40893554688, 40893554688, 40893554688, 70040893554688, 870040893554688, 1870040893554688, 71870040893554688, 871870040893554688 (list; graph; refs; listen; history; text; internal format)
 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 2*a(n) - 1 is divisible by 5^n. - Eric M. Schmidt, Aug 18 2012 LINKS Eric M. Schmidt, Table of n, a(n) for n = 1..1000 Eric Weisstein's World of Mathematics, Automorphic Number PROG (Sage) [crt(0, (5^n + 1)/2, 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012 CROSSREFS Sequence in context: A299671 A299749 A300263 * A109021 A271939 A043043 Adjacent sequences: A030981 A030982 A030983 * A030985 A030986 A030987 KEYWORD nonn,base AUTHOR STATUS approved

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Last modified March 21 18:35 EDT 2023. Contains 361410 sequences. (Running on oeis4.)