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A141709 Least positive multiple of n which is palindromic in base 2, allowing for leading zeros (or: ignoring trailing zeros). 3
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 33, 12, 65, 14, 15, 16, 17, 18, 513, 20, 21, 66, 2047, 24, 325, 130, 27, 28, 1421, 30, 31, 32, 33, 34, 455, 36, 2553, 1026, 195, 40, 1025, 42, 129, 132, 45, 4094, 4841, 48, 1421, 650, 51, 260, 3339, 54, 165, 56, 513, 2842, 6077, 60, 427, 62 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Even numbers cannot be palindromic in base 2, unless leading zeros are considered (or, equivalently, resp. more precisely, trailing zeros are discarded). This is done in this version of A141708, which therefore does not need to be restricted to odd n as it has been done for A141707 and A141708.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

A178225(A000265(a(n))) = 1. - Reinhard Zumkeller, Nov 06 2012

MATHEMATICA

notpalbinQ[i_]:=Module[{id=IntegerDigits[i, 2]}, While[Last[id]==0, id=Most[id]]; id!= Reverse[id]]; lm[n_]:=Module[{k=1}, While[notpalbinQ[k n], k++]; k n]; Array[lm, 70] (* Harvey P. Dale, Dec 28 2011 *)

PROG

(PARI) A141709(n)=forstep(k=n, 10^9, n, vecextract(t=binary(k>>valuation(k, 2)), "-1..1")-t || return(k))

(Haskell)

a141709 n = until ((== 1) . a178225 . a000265) (+ n) n

-- Reinhard Zumkeller, Nov 06 2012

CROSSREFS

Cf. A050782, A141707-A141708, A062279, A203070, A000265, A178225.

Sequence in context: A132579 A004850 A260096 * A062683 A137857 A161980

Adjacent sequences:  A141706 A141707 A141708 * A141710 A141711 A141712

KEYWORD

base,easy,nice,nonn

AUTHOR

M. F. Hasler, Jul 17 2008

STATUS

approved

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Last modified April 19 11:00 EDT 2019. Contains 322259 sequences. (Running on oeis4.)