A008561 - OEIS

A008561

a(1) = 3; a(2) = 11; to get a(n), n >= 3, convert a(n-1) from base 3 to base 2.

3, 11, 100, 1001, 11100, 1110101, 10000100111, 1110011110101001, 1001111011001100001111110, 100010101100001010000100000101000100101, 1001100000001111111111000111111011010101000111001110101000111

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

11 in base 3 is 4 in base 10 which is 100 in base 2.

100 in base 3 is 9 in base 10 which is 1001 in base 2.

MATHEMATICA

Join[{3}, NestList[FromDigits[IntegerDigits[FromDigits[IntegerDigits[#], 3], 2]]&, 11, 10]] (* Harvey P. Dale, Aug 31 2024 *)

CROSSREFS

Very similar to A008560.

Sequence in context: A086914 A123996 A201425 * A348154 A072640 A154299

Adjacent sequences: A008558 A008559 A008560 * A008562 A008563 A008564

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane.

STATUS

approved