Cage order $n(15,12)$

The order of a $(15,12)$-cage, a $15$-regular graph of girth $12$ with the fewest possible vertices.

Lower bound: $1158390$ (1,158,390) Verified (not in the literature)
Upper bound: $1957376$ (1,957,376)

Verified bounds

Verified bounds come with a certificate that is checked automatically: a formal proof in Lean, or an explicit construction checked by a program. Submit a certificate.

Updates from the literature