A390717 Indices in Recamán's sequence A005132 which are the result of a record number of addition steps.

1, 2, 3, 115, 30053, 5026075, 101309269024, 2295517504465252, 26092226183926722, 214195453165357092357, 988968126989839753562465033279585919692224026

Offset

1,2

Comments

A393284 gives corresponding values of A005132.

a(12) > 10^612.

Links

Table of n, a(n) for n=1..11.

Example

Let R(n) = n-th term of Recamán's sequence (A005132). R(111)..R(115) are 40, 152, 265, 379, 494; so R(115)=494 is the result of four consecutive addition steps, and is the first such R(n). Thus a(4) = 115.

Crossrefs

Cf. A005132, A393284 (corresponding terms), A392407 (record subtraction indices), A393285 (record subtraction terms), A057165 (addition steps), A057166 (subtraction steps).

Sequence in context: A084755 A215238 A374873 * A356787 A371146 A127819

Adjacent sequences: A390714 A390715 A390716 * A390718 A390719 A390720

Keyword

nonn

Author

Benjamin Chaffin, Feb 09 2026

Status

approved