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 A297139 Numbers whose base-7 digits d(m), d(m-1),..., d(0) have m=0 or else d(i) = d(i+1) for some i in {0,1,...,m-1}. 4
 1, 2, 3, 4, 5, 6, 8, 16, 24, 32, 40, 48, 49, 56, 57, 58, 59, 60, 61, 62, 65, 73, 81, 89, 97, 98, 106, 112, 113, 114, 115, 116, 117, 118, 122, 130, 138, 146, 147, 155, 163, 168, 169, 170, 171, 172, 173, 174, 179, 187, 195, 196, 204, 212, 220, 224, 225, 226 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS These numbers comprise the complement of the set of numbers in the union of A297137 and A297138. Differs from A044818 first for 344 = 1001_7. 1001_7 has two runs of length 1 and is not in A044818, but it has a sequence of two consecutive zeros and is in this sequence. - R. J. Mathar, Jan 18 2018 LINKS EXAMPLE Base-7 digits of 4998: 2,0,4,0,0, so that 4998 is in the sequence. MAPLE read("transforms") : isA297139 := proc(n)         local dgs, ud;         dgs := convert(n, base, 7) ;         if nops(dgs) < 2 then                 return true;         end if;         if 0 in DIFF(dgs) then                 true;         else                 false;         end if; end proc: for n from 1 to 300 do         if isA297139(n) then                 printf("%d, ", n) ;         end if; end do: # R. J. Mathar, Jan 18 2018 MATHEMATICA a[n_, b_] := Sign[Differences[IntegerDigits[n, b]]]; z = 300; b = 7; t = Table[a[n, b], {n, 1, 10*z}]; u = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == 1 &]   (* A297137 *) v = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == -1 &]  (* A297138 *) Complement[Range[z], Union[u, v]]  (* A297139 *) CROSSREFS Cf. A297137, A297138. Sequence in context: A271949 A039089 A044956 * A044818 A048304 A043710 Adjacent sequences:  A297136 A297137 A297138 * A297140 A297141 A297142 KEYWORD nonn,easy,base AUTHOR Clark Kimberling, Jan 15 2018 STATUS approved

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Last modified January 20 16:32 EST 2022. Contains 350472 sequences. (Running on oeis4.)