3 added 145 characters in body
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V, 26, 16 16, 13 bytes

ä$Àñãxxñh2xVpøˆ±ä$Àñã2xñVpøˆ±

Try it online!

Hexdump:

00000000: e424 c0f1 e378e332 78f1 68325670 7856f888 70f8b1 88b1        .$...xx2x.h2xVpVp...

Try it online! 1 indexed.

Explanation:

ä$                  " Duplicate this line horizontally
  Àñ   ñ            " Arg1 times...
    ã               "   Move to the center of this line
     2x             "   And delete two characters
        V           " Select this whole line
         p          " And replace it with the last pair of characters we deleted
          ø         " Count the number of matches of the following regex...
           <0x88>   "   Any character
                 ±  "   Followed by itself

For reference, my original answer was:

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online! (0 indexed)

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0

V, 26 16 bytes

ä$Àñãxxñh2xVpøˆ±

Hexdump:

00000000: e424 c0f1 e378 78f1 6832 7856 70f8 88b1  .$...xx.h2xVp...

Try it online!

For reference, my original answer was:

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online!

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0

V, 26, 16, 13 bytes

ä$Àñã2xñVpøˆ±

Try it online!

Hexdump:

00000000: e424 c0f1 e332 78f1 5670 f888 b1         .$...2x.Vp...

1 indexed.

Explanation:

ä$                  " Duplicate this line horizontally
  Àñ   ñ            " Arg1 times...
    ã               "   Move to the center of this line
     2x             "   And delete two characters
        V           " Select this whole line
         p          " And replace it with the last pair of characters we deleted
          ø         " Count the number of matches of the following regex...
           <0x88>   "   Any character
                 ±  "   Followed by itself

For reference, my original answer was:

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online! (0 indexed)

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0
2 added 346 characters in body
source | link

V, 2626 16 bytes

ä$Àñãxxñh2xVpøˆ±

Hexdump:

00000000: e424 c0f1 e378 78f1 6832 7856 70f8 88b1  .$...xx.h2xVp...

Try it online!

For reference, my original answer was:

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online!

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0

This is waaaay too long.

V, 26 bytes

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online!

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0

This is waaaay too long.

V, 26 16 bytes

ä$Àñãxxñh2xVpøˆ±

Hexdump:

00000000: e424 c0f1 e378 78f1 6832 7856 70f8 88b1  .$...xx.h2xVp...

Try it online!

For reference, my original answer was:

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online!

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0
1
source | link

V, 26 bytes

Àñx$x|ñxv$hhpÓ¨.©±/1
ñllS0

Try it online!

Hexdump:

00000000: c0f1 7824 787c f178 7624 6868 70d3 a82e  ..x$x|.xv$hhp...
00000010: a9b1 2f31 0af1 6c6c 5330                 ../1..llS0

This is waaaay too long.