A061472 First (leftmost) digit - second digit + third digit - fourth digit .... = 3.

3, 30, 41, 52, 63, 74, 85, 96, 102, 113, 124, 135, 146, 157, 168, 179, 201, 212, 223, 234, 245, 256, 267, 278, 289, 300, 311, 322, 333, 344, 355, 366, 377, 388, 399, 410, 421, 432, 443, 454, 465, 476, 487, 498, 520, 531, 542, 553, 564, 575, 586, 597, 630

Offset: 1

Author

Amarnath Murthy, May 05 2001

Keywords

• nonn
• base
• easy

Examples

			124 is in the sequence since 1 - 2 + 4 = 3.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A008593, A060978-A060980, A060982, A061470-A061479, A061870-A061882, A225693.

Programs

Maple

A225693:= proc(n) local L,m,i;
  L:= convert(n,base,10);
  m:= nops(L);
  add(L[i]*(-1)^(m-i),i=1..m);
end proc:
select(A225693=3, [$1..1000]); # Robert Israel, Jun 12 2019

Mathematica

aQ[n_] := Differences[Total @ Take[IntegerDigits[n], {#, -1, 2}] & /@ {2, 1}][[1]] == 3; Select[Range[1000], aQ] (* Amiram Eldar, Jun 12 2019 *)
Select[Range[1000],Total[Times@@@Partition[Riffle[IntegerDigits[#],{1,-1},{2,-1,2}],2]]==3&] (* Harvey P. Dale, May 16 2020 *)

PARI

isok(n) = my(d=digits(n)); sum(k=1, #d, (-1)^(k+1)*d[k]) == 3; \\ Michel Marcus, Jun 12 2019

Formula

A225693(n) = 3. - Robert Israel, Jun 12 2019

Extensions

More terms from Robert G. Wilson v, May 10 2001 and from Larry Reeves (larryr(AT)acm.org), May 14 2001