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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A319075 Square array T(n,k) read by antidiagonal upwards in which row n lists the n-th powers of primes, hence column k lists the powers of the k-th prime, n >= 0, k >= 1.

Original entry on oeis.org

1, 2, 1, 4, 3, 1, 8, 9, 5, 1, 16, 27, 25, 7, 1, 32, 81, 125, 49, 11, 1, 64, 243, 625, 343, 121, 13, 1, 128, 729, 3125, 2401, 1331, 169, 17, 1, 256, 2187, 15625, 16807, 14641, 2197, 289, 19, 1, 512, 6561, 78125, 117649, 161051, 28561, 4913, 361, 23, 1, 1024, 19683, 390625, 823543, 1771561, 371293
Offset: 0

Views

Author

Omar E. Pol, Sep 09 2018

Keywords

Comments

If n = p - 1 where p is prime, then row n lists the numbers with p divisors.
The partial sums of column k give the column k of A319076.

Examples

			The corner of the square array is as follows:
         A000079 A000244 A000351  A000420    A001020    A001022     A001026
A000012        1,      1,      1,       1,         1,         1,          1, ...
A000040        2,      3,      5,       7,        11,        13,         17, ...
A001248        4,      9,     25,      49,       121,       169,        289, ...
A030078        8,     27,    125,     343,      1331,      2197,       4913, ...
A030514       16,     81,    625,    2401,     14641,     28561,      83521, ...
A050997       32,    243,   3125,   16807,    161051,    371293,    1419857, ...
A030516       64,    729,  15625,  117649,   1771561,   4826809,   24137569, ...
A092759      128,   2187,  78125,  823543,  19487171,  62748517,  410338673, ...
A179645      256,   6561, 390625, 5764801, 214358881, 815730721, 6975757441, ...
...
		

Crossrefs

Other rows n: A030635 (n=16), A030637 (n=18), A137486 (n=22), A137492 (n=28), A139571 (n=30), A139572 (n=36), A139573 (n=40), A139574 (n=42), A139575 (n=46), A173533 (n=52), A183062 (n=58), A183085 (n=60), A261700 (n=100).
Main diagonal gives A093360.
Second diagonal gives A062457.
Third diagonal gives A197987.
Removing the 1's we have A182944/ A182945.

Programs

  • PARI
    T(n, k) = prime(k)^n;

Formula

T(n,k) = A000040(k)^n, n >= 0, k >= 1.

A133356 a(n) = 2*a(n-1) + 16*a(n-2) for n>1, a(0)=1, a(1)=1.

Original entry on oeis.org

1, 1, 18, 52, 392, 1616, 9504, 44864, 241792, 1201408, 6271488, 31765504, 163874816, 835997696, 4293992448, 21963948032, 112631775232, 576686718976, 2955481841664, 15137951186944, 77563611840512, 397334442672128
Offset: 0

Views

Author

Philippe Deléham, Dec 21 2007

Keywords

Comments

Binomial transform of A001026 (powers of 17), with interpolated zeros .

Crossrefs

First differences of A161007.

Programs

Formula

G.f.: (1-x)/(1-2*x-16*x^2).
a(n) = Sum_{k=0..n} A098158(n,k)*17^(n-k). - Philippe Deléham, Dec 26 2007
If p[1]=1, and p[i]=17, (i>1), and if A is Hessenberg matrix of order n defined by: A[i,j] = p[j-i+1], (i<=j), A[i,j] = -1, (i=j+1), and A[i,j]=0 otherwise. Then, for n>=1, a(n)=det A. - Milan Janjic, Apr 29 2010
a(n) = (4*i)^(n-1)*(4*i*ChebyshevU(n, -i/4) - ChebyshevU(n-1, -i/4)) = A161007(n) - A161007(n-1). - G. C. Greubel, Oct 15 2022

A159530 Numerator of Hermite(n, 2/17).

Original entry on oeis.org

1, 4, -562, -6872, 947020, 19676144, -2658183224, -78869600288, 10439530923152, 406451155424320, -52680635240539424, -2560010219314727296, 324703437982090748608, 19055044633095311519488, -2363601454465048638962560, -163647826988867455371547136
Offset: 0

Views

Author

N. J. A. Sloane, Nov 12 2009

Keywords

Crossrefs

The denominators are the powers of 17, A001026.

Programs

  • Magma
    [Numerator((&+[(-1)^k*Factorial(n)*(4/17)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jun 09 2018
  • Mathematica
    Numerator[Table[HermiteH[n,2/17],{n,0,50}]] (* Vladimir Joseph Stephan Orlovsky, Apr 29 2011 *)
  • PARI
    /* needs version >= 2.4 */
    A159530(n)=numerator(polhermite(n,2/17)); /* Joerg Arndt, Apr 30 2011 */
    

Formula

From G. C. Greubel, Jun 02 2018: (Start)
a(n) = 17^n * Hermite(n,2/17).
E.g.f.: exp(4*x-289*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(4/17)^(n-2*k)/(k!*(n-2*k)!)). (End)

A073213 Sum of two powers of 17.

Original entry on oeis.org

2, 18, 34, 290, 306, 578, 4914, 4930, 5202, 9826, 83522, 83538, 83810, 88434, 167042, 1419858, 1419874, 1420146, 1424770, 1503378, 2839714, 24137570, 24137586, 24137858, 24142482, 24221090, 25557426, 48275138, 410338674, 410338690, 410338962, 410343586, 410422194, 411758530, 434476242, 820677346
Offset: 0

Views

Author

Jeremy Gardiner, Jul 20 2002

Keywords

Examples

			T(2,0) = 17^2 + 17^0 = 290.
Table T(n,m) begins:
      2;
     18,    34;
    290,   306,   578;
   4914,  4930,  5202,  9826;
  83522, 83538, 83810, 88434, 167042;
  ...
		

Crossrefs

Cf. A001026 (powers of 17).
Equals twice A073221.
Sums of two powers of n: A073423 (0), A007395 (1), A173786 (2), A055235 (3), A055236 (4), A055237 (5), A055257 (6), A055258 (7), A055259 (8), A055260 (9), A052216 (10), A073211 (11), A194887 (12), A072390 (13), A055261 (16), A073214 (19), A073215 (23).

Programs

  • Mathematica
    Flatten[Table[Table[17^n + 17^m, {m, 0, n}], {n, 0, 7}]] (* T. D. Noe, Jun 18 2013 *)
    Union[Total/@Tuples[17^Range[0,10],2]] (* Harvey P. Dale, Apr 09 2015 *)
  • Python
    from math import isqrt
    def A073213(n): return 17**(a:=(k:=isqrt(m:=n<<1))+(m>k*(k+1))-1)+17**(n-1-(a*(a+1)>>1)) # Chai Wah Wu, Apr 09 2025

Formula

T(n,m) = 17^n + 17^m, n = 0, 1, 2, 3, ..., m = 0, 1, 2, 3, ... n.
Bivariate g.f.: (2 - 18*x)/((1 - x)*(1 - 17*x)*(1 - 17*x*y)). - J. Douglas Morrison, Jul 26 2021

A383809 Consecutive states of a linear congruential pseudo-random number generator for Lisp 1985 when started at 1.

Original entry on oeis.org

1, 17, 38, 144, 189, 201, 154, 108, 79, 88, 241, 81, 122, 66, 118, 249, 217, 175, 214, 124, 100, 194, 35, 93, 75, 20, 89, 7, 119, 15, 4, 68, 152, 74, 3, 51, 114, 181, 65, 101, 211, 73, 237, 13, 221, 243, 115, 198, 103, 245, 149, 23, 140, 121, 49, 80, 105, 28
Offset: 1

Views

Author

Sean A. Irvine, May 17 2025

Keywords

Comments

An example of a terrible random number generator.
Periodic with period 125 (well below the modulus of 251).

Crossrefs

Cf. A001026.
Cf. A096550-A096561 other pseudo-random number generators.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<2, n,
          irem(17*a(n-1), 251))
        end:
    seq(a(n), n=1..58);  # Alois P. Heinz, May 21 2025
  • Mathematica
    NestList[Mod[17*#, 251] &, 1, 100] (* Paolo Xausa, May 21 2025 *)

Formula

a(n) = 17 * a(n-1) mod 251.

A013722 a(n) = 17^(2*n + 1).

Original entry on oeis.org

17, 4913, 1419857, 410338673, 118587876497, 34271896307633, 9904578032905937, 2862423051509815793, 827240261886336764177, 239072435685151324847153, 69091933913008732880827217
Offset: 0

Views

Author

Keywords

Comments

Sum_{n>=0} 1/a(n) = 17/288. - Jaume Oliver Lafont, Feb 04 2009

Crossrefs

Bisection of A001026 (17^n).

Programs

Formula

From Philippe Deléham, Nov 28 2008: (Start)
a(n) = 289*a(n-1), a(0)=17.
G.f.: 17/(1-289*x). (End)

A009978 Powers of 34.

Original entry on oeis.org

1, 34, 1156, 39304, 1336336, 45435424, 1544804416, 52523350144, 1785793904896, 60716992766464, 2064377754059776, 70188843638032384, 2386420683693101056, 81138303245565435904, 2758702310349224820736, 93795878551873643905024, 3189059870763703892770816
Offset: 0

Views

Author

Keywords

Comments

Same as Pisot sequences E(1, 34), L(1, 34), P(1, 34), T(1, 34). Essentially same as Pisot sequences E(34, 1156), L(34, 1156), P(34, 1156), T(34, 1156). See A008776 for definitions of Pisot sequences.
The compositions of n in which each natural number is colored by one of p different colors are called p-colored compositions of n. For n >= 1, a(n) equals the number of 34-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011

Crossrefs

Programs

Formula

G.f.: 1/(1-34*x). - Philippe Deléham, Nov 24 2008
a(n) = 34^n; a(n) = 34*a(n-1), n > 0; a(0)=1. - Vincenzo Librandi, Nov 21 2010
From Elmo R. Oliveira, Jul 10 2025: (Start)
E.g.f.: exp(34*x).
a(n) = A000079(n)*A001026(n). (End)

A180701 Smallest power of 17 that begins with n.

Original entry on oeis.org

1, 289, 34271896307633, 4913, 582622237229761, 6975757441, 7961145753492658188015880378976844387030440651052782229932477774154576998240582422097, 83521, 9904578032905937
Offset: 1

Views

Author

Daniel Mondot, Sep 18 2010

Keywords

Crossrefs

Programs

  • Mathematica
    With[{s=17^Range[0,80]},Table[First[Select[s,First[IntegerDigits[#]]==n&]], {n,9}]] (* Harvey P. Dale, Mar 24 2011 *)

A013806 a(n) = 17^(4*n+1).

Original entry on oeis.org

17, 1419857, 118587876497, 9904578032905937, 827240261886336764177, 69091933913008732880827217, 5770627412348402378939569991057, 481968572106750915091411825223071697, 40254497110927943179349807054456171205137
Offset: 0

Views

Author

Keywords

Comments

As phi(a(n)) = (2*17^n)^4 is a perfect biquadrate (where phi is the Euler totient A000010), this is a subsequence of A078164 and A307690. - Bernard Schott, Mar 29 2022

Crossrefs

Intersection of A001026 and A078164.

Programs

  • Magma
    [17^(4*n+1): n in [0..15]]; // Vincenzo Librandi, Jul 06 2011
  • Mathematica
    17^(4Range[0,10]+1) (* or *) NestList[83521#&,17,20] (* Harvey P. Dale, May 21 2013 *)

Formula

a(0)=17, a(n)=83521*a(n-1). - Harvey P. Dale, May 21 2013
Sum_{n>=0} 1/a(n) = 4913/83520. - Bernard Schott, Mar 29 2022
Sum_{n>=0} (-1)^n/a(n) = 4913/83522. - Bernard Schott, Apr 08 2022

A197351 a(0)=0, a(1)=1, a(2n)=17*a(n), a(2n+1)=a(2n)+1.

Original entry on oeis.org

0, 1, 17, 18, 289, 290, 306, 307, 4913, 4914, 4930, 4931, 5202, 5203, 5219, 5220, 83521, 83522, 83538, 83539, 83810, 83811, 83827, 83828, 88434, 88435, 88451, 88452, 88723, 88724, 88740, 88741, 1419857, 1419858, 1419874, 1419875
Offset: 0

Views

Author

Philippe Deléham, Oct 14 2011

Keywords

Comments

Numbers whose set of base 17 digits is {0,1}.
Sums of distinct powers of 17.
a(n) modulo 2 is the Prouhet-Thue-Morse sequence A010060. - Philippe Deléham, Oct 17 2011.

Crossrefs

Programs

  • Magma
    [n: n in [0..1500000] | Set(IntegerToSequence(n, 17)) subset {0, 1}]; // Vincenzo Librandi, Jun 05 2012
  • Mathematica
    Take[Union[Total/@Subsets[17^Range[0,20],5]],40] (* Harvey P. Dale, Dec 17 2011 *)
    FromDigits[#,17]&/@Tuples[{0,1},5] (* Vincenzo Librandi, Jun 05 2012 *)

Formula

a(n)=Sum_k>=0 {A030308(n,k)*17^k}.
G.f.: (1/(1 - x))*Sum_{k>=0} 17^k*x^(2^k)/(1 + x^(2^k)). - Ilya Gutkovskiy, Jun 04 2017
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