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A020461 as a simple table

na(n)
13
243
3433
4443
53343
63433
733343
8333433
9334333
10343333
11343433
12444343
13444443
143333433
153343343
163343433
173344333
183344443
193433333
203434443
213443443
223444443
234344443
244433333
254434343
264443433
2734333333
2834434343
2934444343
3043444433

[3,43,433,443,3343,3433,33343,333433,334333,
 343333,343433,444343,444443,3333433,3343343,
 3343433,3344333,3344443,3433333,3434443,3443443,
 3444443,4344443,4433333,4434343,4443433,34333333,
 34434343,34444343,43444433]