cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A324475 k appears t+1 times, where t is the number of trailing zeros in A324474(k).

Original entry on oeis.org

1, 2, 3, 3, 4, 4, 5, 5, 5, 6, 7, 7, 7, 8, 9, 9, 9, 9, 10, 11, 12, 12, 13, 13, 13, 13, 14, 15, 16, 16, 17, 17, 17, 17, 17, 18, 19, 20, 20, 21, 21, 22, 22, 22, 23, 24, 24, 24, 24, 24, 25, 26, 27, 27, 28, 28, 29, 29, 29, 30, 31, 31, 31, 31, 31, 31, 32, 33, 34, 34
Offset: 1

Views

Author

Nathan Fox and N. J. A. Sloane, Mar 09 2019

Keywords

Comments

Interesting because the recurrence is nested one layer deeper than the recurrences for A046699 and A316628.

Crossrefs

Cf. A324474.
A046699, A316628, A324473, A324477 have similar definitions.

Programs

  • PARI
    See Links section.

Formula

For n>3, a(n) = a(n-a(n-1)) + a(n-1-a(n-2)-a(n-2-a(n-2))) + a(n-2-a(n-3)-a(n-3-a(n-3)) - a(n-3-a(n-3)-a(n-3-a(n-3)))). - Nathan Fox, Mar 09 2019 (This formula assumes that a(0) = 0. - Rémy Sigrist, Mar 14 2021)

Extensions

Data corrected and more terms from Rémy Sigrist, Mar 14 2021

A324477 k appears t+1 times, where t = A364377(k) is the number of trailing zeros in the greedy Jacobsthal representation of k, A265747(k).

Original entry on oeis.org

1, 2, 3, 3, 4, 5, 5, 5, 6, 7, 8, 8, 9, 10, 10, 10, 11, 11, 11, 11, 12, 13, 14, 14, 15, 16, 16, 16, 17, 18, 19, 19, 20, 21, 21, 21, 21, 21, 22, 23, 24, 24, 25, 26, 26, 26, 27, 28, 29, 29, 30, 31, 31, 31, 32, 32, 32, 32, 33, 34, 35, 35, 36, 37, 37, 37, 38, 39, 40, 40
Offset: 1

Views

Author

Nathan Fox and N. J. A. Sloane, Mar 09 2019

Keywords

Crossrefs

A046699, A316628, A324473 and A324475 have similar definitions.

Programs

  • Mathematica
    Table[Table[k, {IntegerExponent[A265747[k], 10] + 1}], {k, 1, 40}] // Flatten (* Amiram Eldar, Jul 21 2023 using A265747[n] *)

Extensions

More terms from Amiram Eldar, Jul 21 2023

A324473 k appears A278045(k)+1 times.

Original entry on oeis.org

1, 2, 2, 3, 4, 4, 4, 5, 6, 6, 7, 7, 7, 7, 8, 9, 9, 10, 11, 11, 11, 1, 13, 13, 13, 13, 14, 15, 15, 16, 17, 17, 17, 18, 189, 19, 20, 20, 20, 20, 21, 22, 22, 23, 24, 24, 24, 24, 24, 24, 25, 26, 26, 27, 28, 28, 28, 29, 30, 30
Offset: 1

Views

Author

N. J. A. Sloane, Mar 07 2019

Keywords

Comments

Each k appears one more times than the number of trailing zeros in the tribonacci representation of n (see A278038).
This is related to the tribonacci representation of n in the same way as A046699 (without its initial term) is related to the binary representation of n and as A316628 is to the Zeckendorf representation of n.

Crossrefs

Showing 1-3 of 3 results.