A230092 - OEIS

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A230092

Numbers of the form k + wt(k) for exactly three distinct k, where wt(k) = A000120(k) is the binary weight of k.

129, 134, 386, 391, 515, 518, 642, 647, 899, 904, 1028, 1030, 1154, 1159, 1411, 1416, 1540, 1543, 1667, 1672, 1924, 1929, 2178, 2183, 2435, 2440, 2564, 2567, 2691, 2696, 2948, 2953, 3077, 3079, 3203, 3208, 3460, 3465, 3589, 3592, 3716, 3721, 3973, 3978, 4226

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

The positions of entries equal to 3 in A228085, or numbers that appear exactly thrice in A092391.

Numbers that can be expressed as the sum of distinct terms of the form 2^n+1, n=0,1,... in exactly three ways.

LINKS

Reinhard Zumkeller and Donovan Johnson, Table of n, a(n) for n = 1..10000 (first 1000 terms from Reinhard Zumkeller)

Index entries for Colombian or self numbers and related sequences

MAPLE

For Maple code see A230091.

MATHEMATICA