Proposed resolution:

This wording is relative to N4988.

1. Modify [rand.eng.philox], [tab:rand.eng.philox.f] as indicated (This effectively reduces 16 data columns to 4 data columns and 4 data rows to 2 data rows):

   Table 101 — Values for the word permutation f_n(j) [tab:rand.eng.philox.f]

   fn(j)		j
   		0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
   n
   	2	0	1
   	4	20	13	02	31
   	8	2	1	4	7	6	5	0	3
   	16	0	9	2	13	6	11	4	15	10	7	12	3	14	5	8	1

2. Modify [rand.eng.philox] as indicated:

   -4- […]

   1. (4.1) — […]

   2. (4.2) — The following computations are applied to the elements of the V sequence:

      $X_{2k+0}$ = mulhimullo($V_{2k+1}$,$M_k$,w) xor ${\mathrm{key}}_k^q$ xor $V_{2k+1}$

      $X_{2k+1}$ = mullomulhi($V_{2k+1}$,$M_k$,w) xor ${\mathrm{key}}_k^q$ xor $V_{2k}$

   -5- […]

   -6- Mandates:

   1. (6.1) — […]

   2. (6.2) — n == 2 || n == 4 || n == 8 || n == 16 is true, and

   3. (6.3) — […]

   4. (6.4) — […]

3. Modify [rand.predef] as indicated:

   using philox4x32 =
         philox_engine<uint_fast32_t, 32, 4, 10,
          0xCD9E8D570xD2511F53, 0x9E3779B9, 0xD2511F530xCD9E8D57, 0xBB67AE85>;
   

   -11- Required behavior: The 10000^th consecutive invocation a default-constructed object of type philox4x32 produces the value 1955073260.

   using philox4x64 =
         philox_engine<uint_fast64_t, 64, 4, 10,
          0xCA5A8263951211570xD2E7470EE14C6C93, 0x9E3779B97F4A7C15, 0xD2E7470EE14C6C930xCA5A826395121157, 0xBB67AE8584CAA73B>;
   

   -12- Required behavior: The 10000^th consecutive invocation a default-constructed object of type philox4x64 produces the value 3409172418970261260.