A061878 |First digit - second digit + third digit - fourth digit ...| = 9.

9, 90, 108, 119, 207, 218, 229, 306, 317, 328, 339, 405, 416, 427, 438, 449, 504, 515, 526, 537, 548, 559, 603, 614, 625, 636, 647, 658, 669, 702, 713, 724, 735, 746, 757, 768, 779, 801, 812, 823, 834, 845, 856, 867, 878, 889, 900, 911, 922, 933, 944, 955

Offset: 1

Author

Robert G. Wilson v, May 10 2001

Keywords

• nonn
• base
• easy

Comments

Differs from A061478 at the 59th term.

Crossrefs

Cf. A008593, A060978-A060980, A060982, A061470-A061479, A061870-A061882.

Programs

Mathematica

Do[ a = IntegerDigits[ n ]; l = Length[ a ]; e = o = {}; Do[ o = Append[ o, a[ [ 2k - 1 ] ]], {k, 1, l/2 + .5} ]; Do[ e = Append[ e, a[ [ 2k ] ] ], {k, 1, l/2} ]; If[ Abs[ Apply[ Plus, o ] - Apply[ Plus, e ] ] == 9, Print[ n ] ], {n, 1, 1500} ]
ds9Q[n_]:=Module[{idn=IntegerDigits[n],ker}, ker=Table[(-1)^i, {i,2,Length[idn]+1}]; First[ListCorrelate[ker,idn]]==9]; Select[Range[1000],ds9Q]  (* Harvey P. Dale, Feb 14 2011 *)

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), May 15 2001