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01

Shadows of uniform set families

For a finite family F\mathcal F of distinct kk-element sets, let d(F)d(\mathcal F) be the collection of all (k1)(k-1)-element sets contained in at least one member of F\mathcal F, and write D(F)=d(F)D(\mathcal F)=|d(\mathcal F)|. Let M(k)M(k) be the largest positive integer that is not equal to D(F)D(\mathcal F) for any finite family F\mathcal F of distinct kk-element sets.

For fixed kk and tt, let Lk(t)L_k(t) be the smallest integer LL such that every integer from LL through tktk is equal to D(F)D(\mathcal F) for some tt-member family F\mathcal F of distinct kk-element sets. Let τ(k)\tau(k) be the largest tt in {1,,k+1}\{1,\ldots,k+1\} with Lk(t)tkk+2L_k(t)\ge tk-k+2, and let h(k)h(k) be the least integer j0j\ge0 such that (j+32)τ(k)\binom{j+3}{2}\ge \tau(k).

Among the integers kk with 374k25000374\le k\le25000 for which gcd(M(k),τ(k)(h(k)+1))=1\gcd(M(k),\tau(k)(h(k)+1))=1, what is the sum of those kk?