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 A086772 Store the natural numbers in a triangular array such that values on each row have the same number of bits. Start a new row with the smallest number not yet recorded. a(n) represents the initial terms in the resulting array. 1
 0, 1, 3, 4, 7, 9, 15, 21, 24, 31, 41, 45, 63, 64, 72, 74, 83, 94, 127, 139, 140, 173, 197, 207, 234, 255, 268, 284, 288, 339, 349, 390, 426, 445, 467, 511, 522, 553, 569, 634, 689, 706, 734, 797, 838, 934, 950, 951, 1023, 1036, 1052, 1078, 1179, 1236 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A067576 describes the sequences with a fixed number of binary bits using antidiagonals. LINKS EXAMPLE The array begins 0 1 2 3 5 6 4 8 16 32 7 11 13 14 19 9 10 12 17 18 20 15 23 27 29 30 39 43 ... so the initial terms are 0 1 3 4 7 9 15 ... MAPLE A086772aux := proc(n, k)     option remember;     local a, npr, kpr, fnd ;     if n = 0 then         return 0;     end if;     if k = 0 then         for a from 1 do             fnd := false;             for npr from 1 to n-1 do                 for kpr from 0 to npr do                     if procname(npr, kpr) = a then                         fnd := true;                         break;                     end if;                 end do:             end do:             if not fnd then                 return a;             end if;         end do:     else         for a from 1 do             if wt(a) = wt(procname(n, 0)) then                 fnd := false;                 for npr from 1 to n-1 do                     for kpr from 0 to npr do                         if procname(npr, kpr) = a then                             fnd := true;                             break;                         end if;                     end do:                 end do:                 for kpr from 0 to k-1 do                     if procname(n, kpr) = a then                         fnd := true;                         break;                     end if;                 end do:                 if not fnd then                     return a;                 end if;             end if;         end do:     end if; end proc: A086772 := proc(n)     A086772aux(n, 0) ; end proc: # R. J. Mathar, Sep 15 2012 CROSSREFS Cf. A000079, A018900, A014311, A014312, A014313, A023688, A023689, A023690, A023691. Sequence in context: A119907 A241335 A158911 * A301767 A169898 A281734 Adjacent sequences:  A086769 A086770 A086771 * A086773 A086774 A086775 KEYWORD nonn,base AUTHOR Alford Arnold, Aug 03 2003 STATUS approved

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Last modified April 18 22:45 EDT 2021. Contains 343098 sequences. (Running on oeis4.)