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A273158 Number of concatenations nm consisting of n followed by a positive integer m (not a multiple of 10) that are divisible by m. 1
5, 6, 12, 8, 8, 14, 14, 9, 21, 9, 14, 17, 16, 17, 19, 11, 16, 25, 16, 11, 32, 17, 16, 20, 11, 18, 33, 20, 17, 21, 17, 12, 33, 18, 20, 29, 17, 18, 35, 12, 17, 37, 17, 20, 31, 18, 17, 23, 26, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reiner Moewald, Table of n, a(n) for n = 1..98

FORMULA

m <= n * 5^a(2 + floor(log_10(n))) with a(n) from A066343.

EXAMPLE

a(1)=5 since 1|11, 2|12, 5|15, 25|125, 125|1125.

PROG

(Python)

# for N < 100

import math

for N in range (1, 100):

   ANZ = 0

   for M in range(1, 195312500):

      Z = int(str(int(N)) + str(int(M)))

      if ((Z % M == 0) and (M % 10 > 0)):

         ANZ = ANZ + 1

   print(N, ANZ)

CROSSREFS

Cf. A066343.

Sequence in context: A042183 A041939 A177714 * A099641 A207189 A285404

Adjacent sequences:  A273155 A273156 A273157 * A273159 A273160 A273161

KEYWORD

nonn,base

AUTHOR

Reiner Moewald, May 16 2016

STATUS

approved

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Last modified March 25 01:17 EDT 2019. Contains 321450 sequences. (Running on oeis4.)