A167620 Numbers that are multiples of their digital product, where this digital product also appears as their least significant digits.
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 111, 112, 115, 315, 612, 1111, 1112, 1113, 1115, 1116, 11111, 11112, 11115, 12312, 13212, 21312, 23112, 31212, 32112, 111111, 111112, 111115, 111315, 111612, 113115, 116112, 131115, 161112, 311115, 511175
Offset: 1
Examples
612 is in the list because 6*1*2=12, 612 is a multiple of 12, and 12 is the final two digits of 612.
Links
- Karl-Heinz Hofmann, Table of n, a(n) for n = 1..8042 (Terms < 10^18, first 690 terms from David A. Corneth)
Programs
-
PARI
is(n) = { my(vp = vecprod(digits(n))); vp != 0 && n %vp == 0 && n % 10^(#digits(vp)) == vp } \\ David A. Corneth, Mar 30 2021
-
Python
A167620 = [] for k in range(1,511176): dprod, k_str = 1, str(k) for d in range(0,len(k_str)): dprod *= int(k_str[d]) if dprod != 0 and k % dprod == 0 and str(dprod) == k_str[-(len(str(dprod))):]: A167620.append(k) print(A167620) # Karl-Heinz Hofmann, Jan 26 2024
Comments