

A099552


a(n) is the smallest positive integer such that the concatenation of the first n terms is divisible by n.


7



1, 2, 3, 2, 5, 2, 5, 6, 1, 10, 2, 12, 5, 14, 5, 6, 8, 10, 15, 20, 7, 6, 18, 24, 25, 6, 32, 32, 3, 10, 1, 12, 41, 34, 5, 6, 8, 46, 33, 20, 34, 36, 21, 24, 30, 36, 36, 48, 23, 50, 56, 44, 34, 42, 30, 48, 9, 26, 4, 60, 44, 34, 33, 60, 65, 28, 16, 32, 66, 20, 29, 44, 78, 48, 75, 52, 9, 8, 37
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OFFSET

1,2


LINKS



MATHEMATICA

spi[{ctn_, n_, a_}]:=Module[{k=1}, While[Mod[ctn*10^IntegerLength[k]+k, n+1] != 0, k++]; {ctn*10^IntegerLength[k]+k, n+1, k}]; NestList[spi, {1, 1, 1}, 80][[All, 3]] (* Harvey P. Dale, Nov 30 2022 *)


PROG

(PARI) num = 1; print(1); for (n = 2, 9, c = 10*num%n; d = n  c; print(d); num = 10*num + d); for (n = 10, 90, c = 10*num%n; d = n  c; if (d < 10, print(d); num = 10*num + d, c = 100*num%n; d = n  c; if (d < 10, d = d + n); print(d); num = 100*num + d));


CROSSREFS



KEYWORD

base,easy,nonn


AUTHOR



STATUS

approved



