A339216 Numbers k such that k and k+2 are both binary self numbers (A010061).

4, 13, 21, 30, 37, 46, 54, 78, 86, 95, 102, 111, 119, 128, 133, 142, 150, 159, 166, 175, 183, 207, 215, 224, 231, 240, 248, 270, 278, 287, 294, 303, 311, 335, 343, 352, 359, 368, 376, 385, 390, 399, 407, 416, 423, 432, 440, 464, 472, 481, 488, 497, 505, 526, 534

Offset: 1

Author

Amiram Eldar, Nov 27 2020

Keywords

• nonn
• base

Comments

The least difference between consecutive binary self numbers is 2 (see Macris's proof at A010061).

Examples

			4 is a term since 4 and 6 = 4 + 2 are both binary self numbers.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A010061.

Programs

Mathematica

s[n_] := n + DigitCount[n, 2, 1]; m = 550; c = Complement[Range[m], Array[s, m]]; d = Differences[c]; ind = Position[d, 2] // Flatten; c[[ind]]