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A030987
4-automorphic numbers: final digits of 4*n^2 agree with n.
1
4, 44, 344, 7344, 77344, 777344, 6777344, 46777344, 446777344, 446777344, 20446777344, 20446777344, 5020446777344, 35020446777344, 935020446777344, 5935020446777344, 35935020446777344
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 4*a(n) - 1 is divisible by 5^n. - Eric M. Schmidt, Aug 18 2012
PROG
(Sage) [crt(0, (-5^n + 1)/4, 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012
CROSSREFS
Sequence in context: A220920 A035014 A259989 * A341590 A297384 A178294
KEYWORD
nonn,base
STATUS
approved