A333553 a(n) = A333552(A333551(n)): indices of terms in Recamán's sequence A005132 where the construction avoided a record-sized collision.

3, 6, 7, 18, 19, 34, 67, 102, 115, 173, 190, 288, 453, 511, 677, 846, 986, 1230, 1305, 1349, 1715, 2066, 2422, 2870, 3870, 4139, 4599, 4649, 5027, 5899, 7676, 8220, 8742, 9558, 11542, 13144, 13511, 15541, 16001, 16281, 16685, 17199, 18279, 19463, 21267, 23375, 23976, 24260, 24381, 24398, 24399, 55506, 68108, 75688

Offset

1,1

Links

Rémy Sigrist, Table of n, a(n) for n = 1..365

Index entries for sequences related to Recamán's sequence

Rémy Sigrist, C++ program for A333553

Example

After we have found A005132(6)=13, we attempt to subtract 7 from 13 to get a(7). However, this would give 6, which is a collision, since we already have A005132(3)=6. Furthermore, 6 is larger than any collision we have so far avoided. So 7 (the index of the term of A005132 that we were constructing), gets added to the current sequence (it is a(3)).

Prog

(C++) See Links section.

Crossrefs

Cf. A005132, A333548, A333549, A333550, A333551, A333552.

Sequence in context: A334210 A072773 A130049 * A341183 A259256 A056703

Adjacent sequences: A333550 A333551 A333552 * A333554 A333555 A333556

Keyword

nonn

Author

N. J. A. Sloane, May 03 2020, following a suggestion from Paul Zimmermann.

Status

approved