Descending primes

Trivial variation of Ascending primes task.

put (flat 2, 3, 5, 7, sort +*, gather (3..9).map: &recurse ).batch(10)».fmt("%8d").join: "\n";

sub recurse ($str) {
    .take for ($str X~ (1, 3, 7)).grep: { .is-prime && [>] .comb };
    recurse $str × 10 + $_ for 2 ..^ $str % 10;
}

Output:

       2        3        5        7       31       41       43       53       61       71
      73       83       97      421      431      521      541      631      641      643
     653      743      751      761      821      853      863      941      953      971
     983     5431     6421     6521     7321     7541     7621     7643     8431     8521
    8543     8641     8731     8741     8753     8761     9421     9431     9521     9631
    9643     9721     9743     9851     9871    75431    76421    76541    76543    86531
   87421    87541    87631    87641    87643    94321    96431    97651    98321    98543
   98621    98641    98731   764321   865321   876431   975421   986543   987541   987631
 8764321  8765321  9754321  9875321 97654321 98764321 98765431

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