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A043138

Numbers k such that 1 and 3 occur juxtaposed in the base-7 representation of k but not of k-1.

10, 22, 59, 70, 108, 120, 154, 169, 206, 218, 255, 267, 304, 316, 353, 365, 402, 413, 451, 463, 490, 549, 561, 598, 610, 647, 659, 696, 708, 745, 756, 794, 806, 840, 855, 892, 904, 941, 953, 990, 1002, 1039, 1051, 1078, 1137

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..45.

MATHEMATICA

Select[Range[1200], MemberQ[Sort/@Partition[IntegerDigits[#, 7], 2, 1], {1, 3}] && !MemberQ[Sort/@Partition[IntegerDigits[#-1, 7], 2, 1], {1, 3}]&] (* Harvey P. Dale, Aug 10 2011 *)

CROSSREFS

Cf. A007093.

Sequence in context: A039315 A225708 A088871 * A043918 A033459 A255048

Adjacent sequences: A043135 A043136 A043137 * A043139 A043140 A043141

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved