What'd they count?

1+2+3+4+5+6+7+8+9+10+11+12+13 = 91 'steps'

91 steps x 4 'sides' = 364 'steps'

13 x 20 = 260 aka Mayan Tzolkin

14+15+16+17+18+19+20+21+22+23+24+25+26 = 260 'Tzolkin'

26 'letter' alphabet...

260 x 4 = 1040

26 letter alphabet and 52 letter total with lower case.

26 + 26 = 52

52 Mayan century
52 Weeks a modern year
52 Modern Playing cards...