The first 10 solutions for A302980:
  Size of the smallest square Minesweeper grid that allows each number from 0 to 8 appear exactly n times.
  
By Dmitry Kamenetsky, 17/04/2018

a(1)=5
xxx20
x8x41
xxx5x
x76xx
xxxx3

a(2)=7
xxxxxxx
x6xx8xx
3x5xxxx
x35x764
12xxxxx
0247x8x
01xxxxx

a(3)=8
xxxxxx3x
x8x8x7x3
xxxxxxx4
5x8x76xx
xxxxxx64
25x7xxxx
02x5x642
0113xx10

a(4)=9
012xx4x4x
02x7x6x7x
03xxx6xxx
25x8x7x74
xxxxxxxxx
5x8xx8x8x
xxxxxxxxx
24x6x6553
0113x3xx1

a(5)=10
xxx4x4x44x
x8x7x7xxxx
xxxxxxx8x5
x8x8x7xxxx
xxxxxx7x8x
x5567xxxxx
12xxxx6653
013566xxx1
001xxxxx42
001233322x

a(6)=11
1xx4xxx2000
13x6x8x3000
133xxxx4221
x5x7x8x6xx1
xxxxxxxxx42
5x8x8x8x65x
xxxxxxxxxxx
x7x77x76553
x4xxxxxxx4x
2457x8x6x6x
1xxxxxx32xx

a(7)=12
111000002x42
2x3210114xxx
x4xx333x4x7x
36x7xxx45x7x
xxxxx7x5xxxx
x8x8x7x6xx42
xxxxxxxx5320
x8x8x6xx5x21
xxxxx65xx6x3
x7x8xxx6xxxx
x7xxx8x6x8x5
xxx5xxx4xxxx

a(8)=13
02xx3x4x3x4x3
13x55xx5x5xxx
3x6xx6x7x7x8x
xxxxx6xxxxxxx
5x8xx7x767x7x
xxxxxxxxxxxx3
24xx8xx8x765x
125xxxxxxxxx2
1x4x8xx8x8x52
114xxxxxxxx6x
003xxx7xx8xxx
002x6x6xxxx42
00113x4xx4210

a(9)=13
00012xxx11x2x
0002x66544453
0114xxxxxxxxx
01x4x8x8x7664
1336xxxxxxxxx
x3xxx8x8x7x63
25x8xxxxx7x5x
x5xxx8x8xxx6x
x5x8xxxxx7x7x
35xxx7x8x7xxx
xx57x6xxxxx53
23xxx6x7x44x2
013xx4xx212x2

a(10)=14
0001xxx4x4333x
0012456xxxxxx3
001x3xxx8x8x7x
00225x8xxxxxxx
013x6xxx7x8x8x
12xxxx7x7xxxxx
x4457x6xxx8x74
xx4xxx6x7xxxxx
xx6x8x7x7x8x63
3x5xxxxxxxxxx2
13x67xxx8x8x6x
14xxxx5xxxxxx2
1xx6545555x642
13xx2xxxx22xx1