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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Numbers of triangle A027750, written in base 2.

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..7069

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 *)

CROSSREFS

Cf. A007088, A027750, A182621, A182622, A182623, A182624, A182630.

Sequence in context: A288194 A143970 A093645 * A317330 A238880 A340138

Adjacent sequences:  A182617 A182618 A182619 * A182621 A182622 A182623

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

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Last modified April 14 03:53 EDT 2021. Contains 342941 sequences. (Running on oeis4.)