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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
OFFSET
1,1
LINKS
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: A328544 A041939 A177714 * A099641 A207189 A285404
KEYWORD
nonn,base
AUTHOR
Reiner Moewald, May 16 2016
STATUS
approved