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.

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A222172 Total number of ON states after n generations of cellular automaton based on pentagons starting near of the vertex of an infinite 36-degree wedge.

Original entry on oeis.org

0, 1, 2, 3, 5, 8, 10, 11, 13, 17, 21, 24, 29, 36, 40, 41, 43, 47, 53, 61
Offset: 0

Views

Author

Omar E. Pol, Mar 21 2013

Keywords

Comments

The sequence gives the number of pentagons in the structure after n-th stage. A222173 (the first differences) gives the number of pentagons added at n-th stage.
Also P-toothpick sequence starting near of the vertex of an infinite 36-degree wedge, since each pentagon can be replaced by a P-toothpick.
For more information see A222180.
First differs from A153000 at a(9).

Crossrefs

Formula

a(n) = (((A222180(n+2) - 1)/5) - 1)/2 = (A222176(n+1) - 1)/2.
a(n) = (A222180(n+2) - 6)/10. - Omar E. Pol, Nov 24 2013

Extensions

Name improved by Omar E. Pol, Nov 24 2013

A152979 Records in A152978.

Original entry on oeis.org

1, 2, 3, 4, 7, 8, 9, 10, 15, 22, 23, 28, 35, 52, 64, 65, 74, 91, 122, 168, 176, 177, 186, 239, 304, 412, 512, 513, 524, 527, 599, 782, 1020, 1336, 1488, 1489, 1500, 1575, 1980, 2584, 3376, 4160, 4161, 4172, 4174, 4247, 4275, 4653, 5010, 6544, 8544
Offset: 1

Views

Author

Omar E. Pol, Dec 23 2008

Keywords

Comments

This sequence also gives the records in A152980. - Nathaniel Johnston, Apr 10 2011

Crossrefs

Extensions

a(16)-a(51) from Nathaniel Johnston, Apr 10 2011

A159799 First differences of A159789.

Original entry on oeis.org

0, 1, 1, 0, 1, 5, 4, 0, 1, 3, 2, 1, 7, 18, 12, 0, 1, 3, 2, 1, 7, 14, 8, 1, 5, 8, 5, 9, 32, 64, 24, 0, 1, 3, 2, 1, 7, 14, 8, 1, 5, 8, 5, 9, 32, 48, 24, 1, 5
Offset: 1

Views

Author

Omar E. Pol, Jun 13 2009

Keywords

Crossrefs

Formula

a(n) = A159796(n+1)/4.

Extensions

More terms from Colin Barker, Apr 19 2015

A152999 Primes in toothpick sequence A152998.

Original entry on oeis.org

3, 5, 7, 11, 17, 23, 47, 61, 97, 103, 151, 173, 191, 211, 241, 347, 353, 359, 367, 397, 467, 541, 599, 607, 659, 733, 1109, 1237, 1367, 1439, 1453, 1471, 1663, 2029, 2357, 2399, 2671, 2797, 3373, 3607, 3719, 3911, 4241, 5479, 5501, 5527, 5701, 5741, 5779, 5923
Offset: 1

Views

Author

Omar E. Pol, Dec 23 2008

Keywords

Crossrefs

Extensions

More terms from Jinyuan Wang, Mar 15 2020

A160718 a(n) = A160406(n+2)/2.

Original entry on oeis.org

1, 2, 3, 4, 5, 7, 9, 10, 11, 13, 15, 17, 20, 25, 29, 30, 31, 33, 35, 37, 40, 45, 49, 51, 54, 59, 64, 70, 80, 93, 101, 102, 103, 105, 107, 109, 112, 117, 121, 123, 126, 131, 136, 142, 152, 165, 173, 175, 178, 183, 188, 194, 204, 217, 226, 232, 242, 256, 271, 292
Offset: 0

Views

Author

Omar E. Pol, Jun 10 2009

Keywords

Crossrefs

Formula

a(n) = A160719(n) + 1 = -a(n-1) + n + (A139250(n+1) + 5)/4 for n > 0. - Jinyuan Wang, Mar 04 2020

Extensions

More terms from Jinyuan Wang, Mar 04 2020

A160719 a(n) = A160406(n+2)/2 - 1.

Original entry on oeis.org

0, 1, 2, 3, 4, 6, 8, 9, 10, 12, 14, 16, 19, 24, 28, 29, 30, 32, 34, 36, 39, 44, 48, 50, 53, 58, 63, 69, 79, 92, 100, 101, 102, 104, 106, 108, 111, 116, 120, 122, 125, 130, 135, 141, 151, 164, 172, 174, 177, 182, 187, 193, 203, 216, 225, 231, 241, 255, 270, 291
Offset: 0

Views

Author

Omar E. Pol, Jun 10 2009

Keywords

Crossrefs

Extensions

More terms from Jinyuan Wang, Mar 04 2020

A160734 a(n) = (A160158(n+2)-4)/4.

Original entry on oeis.org

0, 1, 3, 5, 6, 8, 11, 13, 15, 19, 25, 30, 33, 38, 43, 45, 47, 51
Offset: 0

Views

Author

Omar E. Pol, Jun 10 2009

Keywords

Crossrefs

A153005 Primes in toothpick sequence A153003.

Original entry on oeis.org

7, 31, 127, 211, 487, 571, 643, 811, 1033, 1249, 1663, 1999, 2131, 2179, 2281, 2347, 2467, 3391, 4801, 5059, 6361, 7759, 8191, 8209, 8713, 8779, 8929, 9187, 9343, 9679, 9931, 10687, 13903, 14947, 19009, 19267, 19423, 25057, 26731, 28879, 33289, 35521
Offset: 1

Views

Author

Omar E. Pol, Jan 02 2009

Keywords

Crossrefs

Programs

  • Maple
    read("transforms3") ; a139250 := BFILETOLIST("b139250.txt") ; A139250 := proc(n) global a139250; op(n+1,a139250) ; end: A153003 := proc(n) if n =0 then 0; else 1+3/4*(A139250(n+1)-3) ; fi; end: for n from 0 to 400 do p := A153003(n) ; if isprime(p) then printf("%d,",p) ; fi; od: # R. J. Mathar, Jul 13 2009
  • Mathematica
    a139250 = Cases[Import["https://oeis.org/A139250/b139250.txt", "Table"], {, }][[All, 2]];
    A139250[n_] := a139250[[n + 1]];
    A153003[n_] := If[n == 0, 0, 1 + 3/4*(A139250[n + 1] - 3)];
    Reap[Do[p = A153003[n]; If[PrimeQ[p], Sow[p]], {n, 0, 400}]][[2, 1]] (* Jean-François Alcover, Apr 05 2020 *)

Extensions

More terms from R. J. Mathar, Jul 13 2009

A153838 Records in A153004.

Original entry on oeis.org

1, 3, 6, 9, 12, 21, 24, 27, 30, 45, 66, 69, 84, 105, 156, 192, 195, 222, 273, 366, 504, 528, 531, 558, 717, 912, 1236, 1536, 1539, 1572, 1581, 1797, 2346, 3060, 4008, 4464, 4467, 4500, 4725, 5940, 7752, 10128, 12480, 12483, 12516, 12522, 12741, 12825, 13959
Offset: 1

Views

Author

Omar E. Pol, Jan 02 2009

Keywords

Crossrefs

Programs

  • Maple
    read("transforms3") : a139250 := BFILETOLIST("b139250.txt") : A139250 := proc(n) global a139250; op(n+1,a139250) ; end: A153003 := proc(n) if n =0 then 0; else 1+3/4*(A139250(n+1)-3) ; fi; end: A153004 := proc(n) A153003(n)-A153003(n-1) ; end: rec := -1 ; for n from 1 to 3000 do t := A153004(n) ; if t > rec then printf("%d,",t) ; rec := t; fi; od: # R. J. Mathar, Jul 13 2009

Extensions

More terms from R. J. Mathar, Jul 13 2009

A168002 Duplicate of A079559.

Original entry on oeis.org

1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1
Offset: 1

Views

Author

Omar E. Pol, Nov 29 2009

Keywords

Comments

Name was: Parity of positive integers of the toothpick sequence in the first quadrant A153000.
Same as A079559: reduce the g.f. of A153000 mod 2 to see this. [Joerg Arndt, Aug 07 2013]

Crossrefs

Formula

a(n) = A000035(A153000(n)). - Omar E. Pol, Aug 06 2013

Extensions

More terms from R. J. Mathar, Dec 04 2009
Previous Showing 21-30 of 31 results. Next