Thanks so much, Hugo I'll add this to the OEIS with both yr name and Perl pgm. Best, E. ------------------------ (...)

Here's some perl code: perl -Mbigint -wle '$n=$a=1; while (1) { print "$n: $a"; ++$n; $a = desc($a) + $a } sub desc { my %a; ++$a{$_} for split //, shift; join "", map +($a{$_}, $_), sort { $a <=> $b } keys %a }'

Compute: 1: 1 2: 12 3: 1124 4: 212338 5: 11434656 6: 2124676182 7: 215338937900 8: 2011338654109729 9: 20314234480170281558 10: 20317265802504533296 11: 50431498946030705115 12: 50834622289546876944 13: 50937835732083050773 14: 50937875857418523592 15: 51038998088873897421 16: 51241110320289174260 17: 81755323561805346079 18: 101966556706331618898 19: 101968597938887792727 20: 102070720070404367576 [...] 25000: 209208887438850939711053 [...] 1718184: 18417097587111721307162018

:Questions: : :- has this seq. a fixed point (or loop)? :- what about other beginnings? :(start with a(1) = 0 for instance)

No: a(n+1) > a(n) is guaranteed by the definition.

See references to "self-describing" in OEIS for some sequences defined along similar lines.

Hugo

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