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A242408 Numbers such that in ternary representation at least one pair of adjacent digits has a sum greater than 2. 4
5, 7, 8, 14, 15, 16, 17, 21, 22, 23, 24, 25, 26, 32, 34, 35, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 86, 88, 89, 95, 96, 97, 98, 102, 103, 104, 105, 106, 107, 113 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A242400(a(n)) > 0;

A242399(a(n)) < 4*a(n).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Ternary.

Wikipedia, Ternary numeral system

EXAMPLE

Initial terms and their ternary representations, cf. A007089:

.  5  7  8  14  15  16  17  21  22  23  24  25  26   32   34   35   41 ..

. 12 21 22 112 120 121 122 210 211 212 220 221 222 1012 1021 1022 1112 ..

MATHEMATICA

Select[Range[200], Max[Total/@Partition[IntegerDigits[#, 3], 2, 1]]>2&] (* Harvey P. Dale, Feb 12 2016 *)

PROG

(Haskell)

a242408 n = a242408_list !! (n-1)

a242408_list = filter ((> 0) . a242400) [0..]

CROSSREFS

Cf. A242407 (complement), A004780.

Sequence in context: A047477 A216555 A288151 * A171952 A238011 A140237

Adjacent sequences:  A242405 A242406 A242407 * A242409 A242410 A242411

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, May 13 2014

STATUS

approved

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Last modified February 20 14:03 EST 2020. Contains 332078 sequences. (Running on oeis4.)