A031232 a(n)=(# 1's)-(# 2's) in first n terms of A031219.

1, 0, 0, 0, 1, 1, 2, 3, 4, 3, 4, 4, 5, 5, 4, 4, 3, 4, 3, 2, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 2, 2, 3, 4, 4, 3, 4, 4, 4, 5, 5, 5, 6, 7, 7, 8, 9, 10, 11, 12, 11, 12, 13, 13, 14, 15, 15, 16, 15, 15, 16, 15, 16, 17, 16

Offset

1,7

Links

Table of n, a(n) for n=1..82.

Mathematica

Accumulate[Which[#==1, 1, #==2, -1, True, 0]&/@Flatten@IntegerDigits[ Range@ 40, 5]] (* Harvey P. Dale, Apr 26 2019 *)

Crossrefs

Sequence in context: A097477 A059572 A031249 * A362024 A030583 A030563

Adjacent sequences: A031229 A031230 A031231 * A031233 A031234 A031235

Keyword

nonn

Author

Clark Kimberling

Status

approved