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15 include "ground/arith/nat_iter.ma".
17 (* RIGHT ADDITION FOR NON-NEGATIVE INTEGERS *********************************)
19 definition nrplus: pnat → nat → pnat ≝
23 "right plus (non-negative integers)"
24 'plus p n = (nrplus p n).
26 (* Basic constructions ******************************************************)
28 lemma nrplus_zero_dx (p): p = p + 𝟎.
31 lemma nrplus_unit_dx (p): ↑p = p + 𝟏.
34 lemma nrplus_succ_sn (p) (n): ↑(p+n) = ↑p + n.
35 #p #n @(niter_appl … psucc)