A379804 By definition, |A379803(k)| is twice a perfect square, say 2*b(k)^2. The values of b(k) appear to be the consecutive natural numbers 1, 2, 3, ... except that the numbers in the present sequence are omitted.

14, 15, 18, 45, 51, 52, 54, 58, 59, 60, 61, 62, 65, 71, 101, 102, 104, 106, 111, 114, 117, 120, 121, 122, 123, 124, 125, 126, 128, 130, 141, 161, 164, 176, 189, 203, 204, 213, 215, 229, 241, 256, 261, 262, 281, 284, 301, 306, 307, 310, 311, 312, 314, 315, 316

Offset: 1

Author

N. J. A. Sloane, Jan 19 2025

Keywords

• nonn

Comments

The sequence {b(k): k >= 1} begins 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16, 17, 19, 20, ..., and as can be seen, 14, 15, and 18 are missing.

The values of b(k) are distinct.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..5000
• Rémy Sigrist, C++ program

Crossrefs

Cf. A377091, A379066, A379788-A379794, A379802, A379803.

Extensions

More terms from Rémy Sigrist, Feb 09 2025