A008467 a(n) = n OR n^2 (applied to ternary expansions).

1, 5, 12, 16, 26, 42, 52, 71, 90, 100, 122, 147, 178, 206, 231, 259, 296, 342, 370, 401, 453, 484, 539, 591, 646, 701, 756, 784, 842, 930, 961, 1025, 1095, 1186, 1259, 1332, 1369, 1445, 1524, 1609, 1691, 1770, 1852, 1943, 2070, 2152, 2237, 2316, 2401, 2510

Offset

1,2

Comments

OR(a, b) = max(a, b) for ternary digits a and b. - Sean A. Irvine, Mar 29 2018

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Maple

a:= proc(n) option remember; local g, h, i, r;
      g, h, r:= n, n^2, 0; for i from 0 while h>0 do
      r:= r + 3^i * max(irem(g, 3, 'g'), irem(h, 3, 'h')) od; r
    end:
seq(a(n), n=1..140);  # Alois P. Heinz, Mar 29 2018

Mathematica

(* program should not be used to extend this sequence *)
b=3; d=9; Mb=Array[ b^(d-#)&, d ]; Map[ Plus@@(Mb*#)&, Array[ Max /@ Transpose[ {IntegerDigits[ #, b, d ], IntegerDigits[ #^2, b, d ]} ]&, 140 ] ]

Crossrefs

Cf. A007745, A008468, A008469.

Sequence in context: A314282 A314283 A342089 * A076718 A076671 A269753

Adjacent sequences: A008464 A008465 A008466 * A008468 A008469 A008470

Keyword

base,nonn,easy

Author

Olivier Gérard

Status

approved