A379803 A377091(k) for k in A379802.

2, 8, -18, -32, 50, 72, -98, -128, -162, 200, 242, 288, 338, 512, -578, 722, 800, 882, 968, -1058, 1152, 1250, 1352, 1458, -1568, 1682, 1800, 1922, -2048, -2178, -2312, 2450, 2592, -2738, -2888, 3042, 3200, -3362, 3528, -3698, -3872, 4232, -4418, -4608, 4802, -5000, 5618, -6050, 6272, -6498, 7938, -8192, 8712, -8978, -9248, 9522, -9800

Offset

1,1

Comments

These are the values of the terms in A377091 that are immediately followed by their negatives.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10001 (first 209 terms from N. J. A. Sloane)

Rémy Sigrist, C++ program

Example

A377091(31) = -18 is immediately followed by A377091(32) = 18, so 31 is a term in A379802, and -18 is in the present sequence.

Mathematica

(* A377091list is defined at A377091 *)
#[[PositionIndex[Differences[Abs[#]]][0]]] & [A377091list[10000]] (* Paolo Xausa, Jan 22 2025 *)

Prog

(C++) // See Links se

Crossrefs

Cf. A377091, A379066, A379788-A379794, A379802, A379804, A380837.

Sequence in context: A074629 A209303 A001105 * A361905 A336489 A051787

Adjacent sequences: A379800 A379801 A379802 * A379804 A379805 A379806

Keyword

sign

Author

N. J. A. Sloane, Jan 19 2025

Status

approved