The Numbers

1+2+3+4+5+6+7+8+9+10+11+12+13 = 91
also known as...
A+B+C+D+E+F+G+H+I+J+K+L+M = 91

14+15+16+17+18+19+20+21+22+23+24+25+26 = 260
and these are also known as...
N+O+P+Q+R+S+T+U+V+W+X+Y+Z = 260


Mayan Tzolkin = 260 'days'
91 'steps' x 4 sides = 364

~ A pyramid has 5 sides though...

91 x 5 = 455