A064531 Number of connected components remaining when decimal expansion of the number n is cut from a piece of paper.

2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 4, 3, 2, 1, 1, 1, 1, 1, 2, 1, 3, 2, 4, 3, 3, 3, 3, 3, 4, 3, 5, 4, 3, 2, 2, 2, 2, 2, 3, 2, 4, 3, 3, 2, 2, 2, 2

Offset

0,1

Comments

Assumes that 4 is represented without a hole.

Links

Table of n, a(n) for n=0..104.

Mathematica

a[n_ /; 0 <= n <= 9] := a[n] = {2, 1, 1, 1, 1, 1, 2, 1, 3, 2}[[n + 1]]; a[n_] := Total[a /@ (id = IntegerDigits[n])] - Length[id] + 1 ; Table[a[n], {n, 0, 104}] (* Jean-François Alcover, Nov 22 2013 *)

Crossrefs

Cf. A064529, A064530. Equals A064532 + 1.

Sequence in context: A025919 A095684 A205565 * A274468 A211993 A185646

Adjacent sequences: A064528 A064529 A064530 * A064532 A064533 A064534

Keyword

nonn,easy,base

Author

N. J. A. Sloane, Oct 07 2001

Extensions

More terms from Matthew Conroy, Oct 09 2001

Status

approved