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|First digit - second digit + third digit - fourth digit ...| = 10.
27

%I #6 Apr 13 2020 15:49:56

%S 109,208,219,307,318,329,406,417,428,439,505,516,527,538,549,604,615,

%T 626,637,648,659,703,714,725,736,747,758,769,802,813,824,835,846,857,

%U 868,879,901,912,923,934,945,956,967,978,989,1090,1209,1308,1319,1407

%N |First digit - second digit + third digit - fourth digit ...| = 10.

%H Harvey P. Dale, <a href="/A060978/b060978.txt">Table of n, a(n) for n = 1..1000</a>

%t 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 ] ] == 10, Print[ n ] ], {n, 1, 2000} ]

%t Select[Range[1500],Abs[Total[Times@@@Partition[Riffle[IntegerDigits[#],{1,-1},{2,-1,2}],2]]]==10&] (* _Harvey P. Dale_, Apr 13 2020 *)

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

%K nonn,base,easy

%O 1,1

%A _Robert G. Wilson v_, May 10 2001