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A356176
Numbers that can be written as the product of three divisors greater than 1 such that the number in binary is contained in the string concatenation of the divisors in binary.
2
30, 60, 63, 90, 110, 120, 126, 180, 220, 228, 240, 252, 340, 350, 430, 440, 480, 495, 504, 606, 612, 680, 759, 840, 860, 880, 891, 927, 957, 960, 990, 1008, 1212, 1224, 1320, 1526, 1710, 1720, 1755, 1760, 1782, 1854, 1920, 1980, 2016, 2376, 2424, 2466, 2640, 2925, 2955, 2990, 3045, 3050
OFFSET
1,1
COMMENTS
See A356143 for the list of numbers that have two or more ways to be written as the product of three divisors such that the number in binary is contained in the string concatenation of the divisors in binary.
EXAMPLE
30 is a term as 30 = 11110_2 = 5 * 3 * 2 = 101_2 * 11_2 * 10_2 and "101" + "11" + "10" = "1011110" contains "11110".
3050 is a term as 3050 = 101111101010_2 = 5 * 122 * 5 = 101_2 * 1111010_2 * 101_2 and "101" + "1111010" + "101" = "1011111010101" contains "101111101010".
See the attached text file for other examples.
KEYWORD
nonn,base
AUTHOR
Scott R. Shannon, Jul 28 2022
STATUS
approved