English
Analogous to lists, the sum of a multiset of finsupps has support contained in the supremum of mapped supports.
Русский
Аналогично спискам, сумма мультимножества финспп имеет опору внутри супремума приведённых опор.
LaTeX
$$$\\operatorname{supp}(\\\\operatorname{sum} s) \\\\subseteq (\\\\operatorname{map}\\\\ Finsupp.\\\\operatorname{support} s) \\\\mathsf{sup}$$$
Lean4
theorem support_sum_subset [AddCommMonoid M] (s : Multiset (ι →₀ M)) : s.sum.support ⊆ (s.map Finsupp.support).sup :=
by
induction s using Quot.inductionOn
simpa only [Multiset.quot_mk_to_coe'', Multiset.sum_coe, Multiset.map_coe, Multiset.sup_coe, List.foldr_map] using
List.support_sum_subset _