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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
OFFSET
1,1
COMMENTS
A242400(a(n)) > 0;
A242399(a(n)) < 4*a(n).
LINKS
Eric Weisstein's World of Mathematics, Ternary.
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
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, May 13 2014
STATUS
approved