A032987 Numbers with the property that all pairs of consecutive base-10 digits differ by more than 2.

1, 2, 3, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17, 18, 19, 25, 26, 27, 28, 29, 30, 36, 37, 38, 39, 40, 41, 47, 48, 49, 50, 51, 52, 58, 59, 60, 61, 62, 63, 69, 70, 71, 72, 73, 74, 80, 81, 82, 83, 84, 85, 90, 91, 92, 93, 94, 95, 96, 140, 141, 147, 148

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

for i from 0 to 9 do S[1, i]:= {i} od:
for d from 2 to 3 do
  for i from 0 to 9 do
    S[d, i]:=  `union`(seq(map(t -> i*10^(d-1)+t, S[d-1, j]), j={$0..9} minus {$(i-2)..(i+2)}))
od od:
[seq(seq(op(sort(convert(S[d, i], list))), i=1..9), d=1..3)]; # Robert Israel, Sep 28 2025

Mathematica

Select[Range[200], And@@(Abs[First[#]-Last[#]]>2&/@Partition[ IntegerDigits[#], 2, 1])&] (* Harvey P. Dale, Mar 28 2011 *)
Select[Range[200], Min[Abs[Differences[IntegerDigits[#]]]]>2&] (* Harvey P. Dale, May 24 2015 *)

Crossrefs

Cf. A032981.

Sequence in context: A244155 A066310 A342226 * A174876 A092597 A335134

Adjacent sequences: A032984 A032985 A032986 * A032988 A032989 A032990

Keyword

nonn,base

Author

Clark Kimberling

Status

approved