A075017 Smallest k such that the concatenation k, k+1,k+2,k+3 is divisible by n; or 0 if no such number exists.

1, 1, 3, 3, 2, 3, 2, 3, 3, 7, 8, 3, 7, 17, 12, 3, 5, 3, 19, 17, 24, 15, 17, 3, 22, 7, 3, 17, 17, 27, 6, 3, 15, 5, 2, 3, 9, 19, 15, 17, 15, 45, 44, 37, 12, 17, 39, 3, 45, 47, 21, 41, 52, 3, 37, 17, 57, 17, 62, 57, 53, 53, 66, 3, 7, 15, 2, 21, 63, 17, 12, 3, 6, 9, 72

Offset

1,3

Links

Table of n, a(n) for n=1..75.

Example

a(7) = 2 as 7 divides 2345.

Prog

(PARI) isok(k, n) = my(v = Str(k)); for (j=1, 3, v = concat(v, Str(k+j))); (eval(v) % n) == 0;
a(n) = my(k=1); while (!isok(k, n), k++); k; \\ Michel Marcus, Jan 21 2017

Crossrefs

Cf. A075113, A075114, A075115, A075116.

Sequence in context: A260896 A365711 A237347 * A060586 A076662 A164359

Adjacent sequences: A075014 A075015 A075016 * A075018 A075019 A075020

Keyword

base,nonn

Author

Amarnath Murthy, Sep 01 2002

Extensions

Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 19 2003

Status

approved