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A100761
Beginning with 1, the smallest positive number which when appended to the reverse concatenation of all previous terms gives a multiple of n.
0
1, 2, 3, 2, 5, 2, 3, 6, 3, 10, 4, 16, 22, 6, 5, 6, 2, 10, 15, 20, 25, 30, 12, 6, 25, 2, 9, 2, 2, 20, 34, 28, 16, 22, 30, 44, 17, 46, 48, 20, 47, 44, 34, 32, 45, 24, 35, 28, 38, 50, 47, 24, 1, 50, 20, 36, 1, 34, 51, 20, 35, 34, 66, 28, 60, 38, 16, 32, 33, 50, 3, 28, 66, 66, 75, 12, 4, 26
OFFSET
1,2
EXAMPLE
a(2) = 2, 2 divides 12, a(3) = 3, 213 is a multiple of 3, a(4) = 2, 3212 is a multiple of 4.
a(11) = 4, 103632523214 == 0 (mod 11) where 103632523214 is 10363252321 followed by a 4.
MATHEMATICA
a[1] = 1; a[n_] := a[n] = Block[{k = 1, t = Flatten[ Table[ IntegerDigits[ a[n - i]], {i, n - 1}]]}, While[ Mod[ FromDigits[ Join[t, IntegerDigits[k]]], n] != 0, k++ ]; k]; Table[ a[n], {n, 78}] (* Robert G. Wilson v, Nov 26 2004 *)
CROSSREFS
Sequence in context: A087986 A129088 A086418 * A336964 A027748 A361650
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 25 2004
EXTENSIONS
More terms from Robert G. Wilson v, Nov 26 2004
STATUS
approved