A273158 Number of concatenations nm consisting of n followed by a positive integer m (not a multiple of 10) that are divisible by m.

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

Offset: 1

Author

Reiner Moewald, May 16 2016

Keywords

• nonn
• base

Examples

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

Links

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

Crossrefs

Cf. A066343.

Programs

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)

Formula

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