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A182620
Triangle T(n,k) read by rows in which row n lists the divisors of n, written in base 2.
7
1, 1, 10, 1, 11, 1, 10, 100, 1, 101, 1, 10, 11, 110, 1, 111, 1, 10, 100, 1000, 1, 11, 1001, 1, 10, 101, 1010, 1, 1011, 1, 10, 11, 100, 110, 1100, 1, 1101, 1, 10, 111, 1110, 1, 11, 101, 1111, 1, 10, 100, 1000, 10000, 1, 10001, 1, 10, 11
OFFSET
1,3
COMMENTS
Numbers of triangle A027750, written in base 2.
LINKS
FORMULA
T(n,k) = A007088(A027750(n,k)).
EXAMPLE
The divisors of 10 are 1, 2, 5, 10 then row 10 lists the binary numbers 1, 10, 101, 1010.
Triangle begins:
1,
1, 10,
1, 11,
1, 10, 100,
1, 101,
1, 10, 11, 110,
1, 111,
1, 10, 100, 1000,
1, 11, 1001,
1, 10, 101, 1010,
1, 1011,
1, 10, 11, 100, 110, 1100,
MAPLE
with(numtheory):for n from 1 to 10 do for d in divisors(n) do printf("%d, ", convert(d, binary)); od:printf("\n"); od: # Nathaniel Johnston, Apr 19 2011
MATHEMATICA
Table[FromDigits[IntegerDigits[#, 2]]&/@Divisors[n], {n, 20}]//Flatten (* Harvey P. Dale, May 31 2018 *)
KEYWORD
nonn,easy,tabf,base
AUTHOR
Omar E. Pol, Nov 22 2010
EXTENSIONS
a(38)-a(55) from Nathaniel Johnston, Apr 19 2011
STATUS
approved