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 1-4 of 4 results.

A085836 Final terms of rows of A085612.

Original entry on oeis.org

1, 3, 25, 13, 21, 2197, 50, 130321, 47, 55, 189, 154, 115856201, 2601, 656, 4489, 172, 137, 118, 340, 151334226289, 7803, 2336, 202, 945, 107213535210701, 281, 44944, 374, 436, 2196, 7232, 305, 1590, 1685159, 1048, 2960, 498311414318121121, 523
Offset: 1

Views

Author

Alford Arnold, Jul 04 2003

Keywords

Links

Crossrefs

Cf. A085612, A085834.

Extensions

More terms from David Wasserman, Feb 10 2005

A085834 Initial terms of rows in table A085612.

Original entry on oeis.org

1, 2, 4, 5, 6, 8, 12, 16, 17, 22, 24, 30, 32, 36, 48, 49, 52, 53, 57, 60, 64, 72, 96, 119, 120, 128, 139, 144, 165, 175, 180, 192, 203, 210, 216, 232, 240, 256, 283, 288, 309, 342, 360, 384, 385, 420, 432, 452, 454, 480, 512, 541, 576, 626, 663, 688, 720, 768
Offset: 1

Views

Author

Alford Arnold, Jul 04 2003

Keywords

Comments

The least prime signature sequence (A025487) is embedded in this sequence.

Links

Crossrefs

Cf. A025487, A085612, A085836.

Extensions

More terms from Amiram Eldar, Jun 28 2025

A224401 a(n) is the row number of triangle A085612 in which n appears.

Original entry on oeis.org

1, 2, 2, 3, 4, 5, 4, 6, 3, 5, 4, 7, 4, 5, 5, 8, 9, 7, 9, 7, 5, 10, 9, 11, 3, 10, 6, 7, 9, 12, 9, 13, 10, 10, 10, 14, 9, 10, 10, 11, 9, 12, 9, 7, 7, 10, 9, 15, 16, 7, 10, 17, 18, 11, 10, 11, 19, 19, 18, 20, 18, 19, 17, 21, 19, 12, 18, 17, 19, 12, 18, 22, 18, 19
Offset: 1

Views

Author

Matthew Goers, Apr 05 2013

Keywords

Comments

Row number in A085612 triangle of prime signatures.
a(n) is not the same for all numbers n with the same prime signature. For such a sequence, see A101296. - Peter Munn, Oct 23 2023

Examples

			a(9) = 3, because 9 is in the 3rd row (1st 3 prime^2) of A085612.
a(10) = 5, because 10 is in the 5th row (1st 5 semiprimes) of A085612.
a(11) = 4, because 11 is in the 4th row (4 primes, prime(3)..prime(6)) of A085612.

Links

Crossrefs

Cf. A085612, A101296.
First and last positions of each number: A085834, A085836.

Programs

  • Haskell
    import Data.List (findIndex); import Data.Maybe (fromJust)
a224401 = (+ 1) . fromJust . (`findIndex` a085612_tabf) . elem
-- Reinhard Zumkeller, Jun 05 2013
  • PARI
    See Links section.

A226387 Inverse permutation to A085612.

Original entry on oeis.org

1, 2, 3, 4, 7, 11, 8, 16, 5, 12, 9, 22, 10, 13, 14, 29, 37, 23, 38, 24, 15, 46, 39, 56, 6, 47, 17, 25, 40, 67, 41, 79, 48, 49, 50, 92, 42, 51, 52, 57, 43, 68, 44, 26, 27, 53, 45, 106, 121, 28, 54, 137, 154, 58, 55, 59, 172, 173, 155, 191, 156, 174, 138, 211
Offset: 1

Views

Author

Reinhard Zumkeller, Jun 05 2013

Keywords

Links

Crossrefs

Cf. A224401.

Programs

  • Haskell
    import Data.List (elemIndex); import Data.Maybe (fromJust)
a226387 = (+ 1) . fromJust . (`elemIndex` a085612_list)
  • PARI
    See Links section.

Extensions

More terms from Rémy Sigrist, Apr 25 2021
Showing 1-4 of 4 results.

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