|
Search: id:A076643
|
|
|
| A076643 |
|
Integers read backwards, but omit a number if it is <= an earlier number. |
|
+0
1
|
|
| 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 21, 31, 41, 51, 61, 71, 81, 91, 92, 93, 94, 95, 96, 97, 98, 99, 101, 201, 301, 401, 501, 601, 701, 801, 901, 911, 921, 931, 941, 951, 961, 971, 981, 991, 992, 993, 994, 995, 996, 997, 998, 999, 1001, 2001, 3001, 4001, 5001, 6001, 7001
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
EXAMPLE
|
The beginning list is 1,2,3,4,5,6,7,8,9,1,11; but 1<9 so omit it.
|
|
MAPLE
|
d := N->`if`(N=0, [0], ListTools[Reverse](convert(N, base, 10))); a := N->sum(d(N)[n]*10^(n-1), n=1..nops(d(N))); dropsort := proc(S)::list; description "Forms a strictly increasing list by dropping terms."; local T, V; T := k->max(seq(S[j], j=1..k)); V := ListTools[MakeUnique]([seq(T(j), j=1..nops(S))]); return(V); end proc; dropsort([seq(a(n), n=1..2000)]);
|
|
CROSSREFS
|
Cf. A004086.
Sequence in context: A161390 A096106 A076641 this_sequence A127204 A102235 A107272
Adjacent sequences: A076640 A076641 A076642 this_sequence A076644 A076645 A076646
|
|
KEYWORD
|
easy,nonn,base
|
|
AUTHOR
|
Francois Jooste (phukraut(AT)hotmail.com), Oct 23 2002
|
|
|
Search completed in 0.002 seconds
|
