login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

A031250 as a simple table

na(n)
10
20
31
40
50
60
70
80
90
100
111
121
130
140
150
160
170
180
190
200
211
221
230
240
250
261
271
282
292
303
314
325
334
345
355
364
374
383
393
402
413
422
431
440
450
460
470
480
490
500
510
520
530
541
551
561
570
580
590
600
610
620
630
640
650
660
670
680
691
701
711
720
730
740
750
760
770
780
790
800
810
820
830
841
851
861
870
880
890
900

[0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,1,1,0,0,
 0,1,1,2,2,3,4,5,4,5,5,4,4,3,3,2,3,2,1,0,0,0,0,0,0,
 0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,
 0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0]