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A162213 a(n) = the smallest positive multiple of n with exactly n digits when written in binary. 1
1, 2, 6, 8, 20, 36, 70, 128, 261, 520, 1034, 2052, 4108, 8204, 16395, 32768, 65552, 131076, 262162, 524300, 1048593, 2097172, 4194326, 8388624, 16777225, 33554456, 67108878, 134217748, 268435484, 536870940, 1073741854, 2147483648 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a(n) = n * ceiling (2^(n-1)/n). [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Jul 11 2009]

MAPLE

a := proc (n) local k: for k while nops(convert(k*n, base, 2)) <> n do end do; k*n end proc: seq(a(n), n = 1 .. 24); [From Emeric Deutsch (deutsch(AT)duke.poly.edu), Jul 10 2009]

a:= n-> n *ceil (2^(n-1)/n): seq (a(n), n=1..40); [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Jul 11 2009]

CROSSREFS

A162214

Sequence in context: A143481 A093968 A064713 * A100358 A134136 A185165

Adjacent sequences:  A162210 A162211 A162212 * A162214 A162215 A162216

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jun 28 2009

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu) and Alois P. Heinz (heinz(AT)hs-heilbronn.de), Jul 11 2009

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Last modified February 14 18:47 EST 2012. Contains 205663 sequences.