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 1-5 of 5 results.

A138420 a(n) = ((prime(n))^4-(prime(n))^2)/4.

Original entry on oeis.org

3, 18, 150, 588, 3630, 7098, 20808, 32490, 69828, 176610, 230640, 468198, 706020, 854238, 1219368, 1971918, 3028470, 3460530, 5036658, 6351660, 7098228, 9735960, 11862858, 15683580, 22129968, 26012550, 28135068, 32767038, 35286570
Offset: 1

Views

Author

Artur Jasinski, Mar 19 2008

Keywords

Comments

Number of monic irreducible polynomials of degree 4 over GF(prime(n)). - Robert Israel, Jan 07 2015

Crossrefs

Programs

  • Magma
    [(NthPrime((n))^4 - NthPrime((n))^2)/4: n in [1..30] ]; // Vincenzo Librandi, Jun 17 2011
    
  • Maple
    seq(1/4*(ithprime(i)^4 - ithprime(i)^2), i=1..100); # Robert Israel, Jan 07 2015
  • Mathematica
    a = {}; Do[p = Prime[n]; AppendTo[a, (p^4 - p^2)/4], {n, 1, 50}]; a
    (#^4-#^2)/4&/@Prime[Range[30]] (* Harvey P. Dale, Aug 01 2025 *)
  • PARI
    forprime(p=2,1e3,print1((p^4-p^2)/4", ")) \\ Charles R Greathouse IV, Jul 15 2011

Formula

a(n) = A138402(n)/4. - R. J. Mathar, Oct 15 2017

Extensions

Name edited by Robert Israel, Jan 07 2015

A138416 a(n) = (p^3 - p^2)/2, where p = prime(n).

Original entry on oeis.org

2, 9, 50, 147, 605, 1014, 2312, 3249, 5819, 11774, 14415, 24642, 33620, 38829, 50807, 73034, 100949, 111630, 148137, 176435, 191844, 243399, 282449, 348524, 451632, 510050, 541059, 606797, 641574, 715064, 1016127, 1115465, 1276292, 1333149
Offset: 1

Views

Author

Artur Jasinski, Mar 19 2008

Keywords

Comments

Differences (p^k - p^m)/q with k > m:
expression OEIS sequence
-------------- -------------
p^2 - p A036689
(p^2 - p)/2 A008837
p^3 - p A127917
(p^3 - p)/2 A127918
(p^3 - p)/3 A127919
(p^3 - p)/6 A127920
p^3 - p^2 A135177
(p^3 - p^2)/2 this sequence
p^4 - p A138401
(p^4 - p)/2 A138417
p^4 - p^2 A138402
(p^4 - p^2)/2 A138418
(p^4 - p^2)/3 A138419
(p^4 - p^2)/4 A138420
(p^4 - p^2)/6 A138421
(p^4 - p^2)/12 A138422
p^4 - p^3 A138403
(p^4 - p^3)/2 A138423
p^5 - p A138404
(p^5 - p)/2 A138424
(p^5 - p)/3 A138425
(p^5 - p)/5 A138426
(p^5 - p)/6 A138427
(p^5 - p)/10 A138428
(p^5 - p)/15 A138429
(p^5 - p)/30 A138430
p^5 - p^2 A138405
(p^5 - p^2)/2 A138431
p^5 - p^3 A138406
(p^5 - p^3)/2 A138432
(p^5 - p^3)/3 A138433
(p^5 - p^3)/4 A138434
(p^5 - p^3)/6 A138435
(p^5 - p^3)/8 A138436
(p^5 - p^3)/12 A138437
(p^5 - p^3)/24 A138438
p^5 - p^4 A138407
(p^5 - p^4)/2 A138439
p^6 - p A138408
(p^6 - p)/2 A138440
p^6 - p^2 A138409
(p^6 - p^2)/2 A138441
(p^6 - p^2)/3 A138442
(p^6 - p^2)/4 A138443
(p^6 - p^2)/5 A138444
(p^6 - p^2)/6 A138445
(p^6 - p^2)/10 A138446
(p^6 - p^2)/12 A138447
(p^6 - p^2)/15 A138448
(p^6 - p^2)/20 A122220
(p^6 - p^2)/30 A138450
(p^6 - p^2)/60 A138451
p^6 - p^3 A138410
(p^6 - p^3)/2 A138452
p^6 - p^4 A138411
(p^6 - p^4)/2 A138453
(p^6 - p^4)/3 A138454
(p^6 - p^4)/4 A138455
(p^6 - p^4)/6 A138456
(p^6 - p^4)/8 A138457
(p^6 - p^4)/12 A138458
(p^6 - p^4)/24 A138459
p^6 - p^5 A138412
(p^6 - p^5)/2 A138460
.
We can prove that for n>1, a(n) is the remainder of the Euclidean division of Sum_{k=0..p-1} k^p by p^3 where p = prime(n). - Pierre Vandaƫle, Nov 30 2024

Programs

  • Magma
    [(p^3-p^2)/2: p in PrimesUpTo(1000)]; // Vincenzo Librandi, Jun 17 2011
  • Mathematica
    a = {}; Do[p = Prime[n]; AppendTo[a, (p^3 - p^2)/2], {n, 1, 50}]; a
    (#^3-#^2)/2&/@Prime[Range[50]] (* Harvey P. Dale, Nov 01 2020 *)
  • PARI
    forprime(p=2,1e3,print1((p^3-p^2)/2", ")) \\ Charles R Greathouse IV, Jun 16 2011
    

Extensions

Definition corrected by T. D. Noe, Aug 25 2008

A138430 a(n) = (prime(n)^5 - prime(n))/30.

Original entry on oeis.org

1, 8, 104, 560, 5368, 12376, 47328, 82536, 214544, 683704, 954304, 2311464, 3861872, 4900280, 7644832, 13939848, 23830808, 28153208, 45004168, 60140976, 69102384, 102568544, 131301352, 186135312, 286244672, 350336680, 386424688, 467517240, 512874648
Offset: 1

Views

Author

Artur Jasinski, Mar 19 2008

Keywords

Comments

a(n) = Sum_{i+j=p} (i^2)*(j^2) where p = prime(n). - Michel Lagneau, May 21 2012

Crossrefs

Programs

  • Magma
    [(NthPrime((n))^5 - NthPrime((n)))/30: n in [1..30]]; // Vincenzo Librandi, Jun 18 2011
    
  • Mathematica
    Table[p = Prime[n]; (p^5 - p)/30, {n, 50}]
  • PARI
    forprime(p=2,1e3,print1((p^5-p)/30", ")) \\ Charles R Greathouse IV, Jul 15 2011

Formula

a(n) = A138404(n)/30. - R. J. Mathar, Oct 15 2017
a(n) = A138426(n)/6. - Bernard Schott, Feb 28 2023

A138459 a(n) = ((n-th prime)^6-(n-th prime)^4)/12.

Original entry on oeis.org

4, 54, 1250, 9604, 146410, 399854, 2004504, 3909630, 12313004, 49509670, 73881680, 213654354, 395606540, 526495354, 897861304, 1846372554, 3514034690, 4292210710, 7536519254, 10672906020, 12608819004, 20254042120, 27241076254
Offset: 1

Views

Author

Artur Jasinski, Mar 22 2008

Keywords

Comments

Differences (p^k-p^m)/q such that k > m:
p^2-p is given in A036689
(p^2-p)/2 is given in A008837
p^3-p is given in A127917
(p^3-p)/2 is given in A127918
(p^3-p)/3 is given in A127919
(p^3-p)/6 is given in A127920
p^3-p^2 is given in A135177
(p^3-p^2)/2 is given in A138416
p^4-p is given in A138401
(p^4-p)/2 is given in A138417
p^4-p^2 is given in A138402
(p^4-p^2)/2 is given in A138418
(p^4-p^2)/3 is given in A138419
(p^4-p^2)/4 is given in A138420
(p^4-p^2)/6 is given in A138421
(p^4-p^2)/12 is given in A138422
p^4-p^3 is given in A138403
(p^4-p^3)/2 is given in A138423
p^5-p is given in A138404
(p^5-p)/2 is given in A138424
(p^5-p)/3 is given in A138425
(p^5-p)/5 is given in A138426
(p^5-p)/6 is given in A138427
(p^5-p)/10 is given in A138428
(p^5-p)/15 is given in A138429
(p^5-p)/30 is given in A138430
p^5-p^2 is given in A138405
(p^5-p^2)/2 is given in A138431
p^5-p^3 is given in A138406
(p^5-p^3)/2 is given in A138432
(p^5-p^3)/3 is given in A138433
(p^5-p^3)/4 is given in A138434
(p^5-p^3)/6 is given in A138435
(p^5-p^3)/8 is given in A138436
(p^5-p^3)/12 is given in A138437
(p^5-p^3)/24 is given in A138438
p^5-p^4 is given in A138407
(p^5-p^4)/2 is given in A138439
p^6-p is given in A138408
(p^6-p)/2 is given in A138440
p^6-p^2 is given in A138409
(p^6-p^2)/2 is given in A138441
(p^6-p^2)/3 is given in A138442
(p^6-p^2)/4 is given in A138443
(p^6-p^2)/5 is given in A138444
(p^6-p^2)/6 is given in A138445
(p^6-p^2)/10 is given in A138446
(p^6-p^2)/12 is given in A138447
(p^6-p^2)/15 is given in A138448
(p^6-p^2)/20 is given in A122220
(p^6-p^2)/30 is given in A138450
(p^6-p^2)/60 is given in A138451
p^6-p^3 is given in A138410
(p^6-p^3)/2 is given in A138452
p^6-p^4 is given in A138411
(p^6-p^4)/2 is given in A138453
(p^6-p^4)/3 is given in A138454
(p^6-p^4)/4 is given in A138455
(p^6-p^4)/6 is given in A138456
(p^6-p^4)/8 is given in A138457
(p^6-p^4)/12 is given in A138458
(p^6-p^4)/24 is given in A138459
p^6-p^5 is given in A138412
(p^6-p^5)/2 is given in A138460

Programs

  • Mathematica
    a = {}; Do[p = Prime[n]; AppendTo[a, (p^6 - p^4)/12], {n, 1, 24}]; a
  • PARI
    forprime(p=2,1e3,print1((p^6-p^4)/12", ")) \\ Charles R Greathouse IV, Jul 15 2011

A253655 Number of monic irreducible polynomials of degree 6 over GF(prime(n)).

Original entry on oeis.org

9, 116, 2580, 19544, 295020, 804076, 4022064, 7839780, 24670536, 99133020, 147912160, 427612404, 791672280, 1053546956, 1796518224, 3694034916, 7030054140, 8586690620, 15076346164, 21349986840, 25222305336, 40514492720, 54489965796, 82830096360, 138828513824, 176919851700
Offset: 1

Views

Author

Robert Israel, Jan 07 2015

Keywords

Examples

			For n=1 the a(1) = 9 irreducible monic polynomials of degree 6 over GF(2) are
x^6+x^5+1, x^6+x^3+1, x^6+x^5+x^4+x^2+1, x^6+x^5+x^3+x^2+1, x^6+x+1, x^6+x^5+x^4+x+1, x^6+x^4+x^3+x+1, x^6+x^5+x^2+x+1, x^6+x^4+x^2+x+1.
		

Crossrefs

Programs

  • Magma
    [(p^6 - p^3 - p^2 + p) div 6: p in PrimesUpTo(110)]; // Vincenzo Librandi, Jan 08 2015
  • Maple
    f:= p-> (p^6 - p^3 - p^2 + p)/6:
    seq(f(ithprime(i)), i=1..100); # Robert Israel, Jan 07 2015
  • Mathematica
    Table[(Prime[n]^6 - Prime[n]^3 - Prime[n]^2 + Prime[n]) / 6, {n, 1, 30}] (* Vincenzo Librandi, Jan 08 2015 *)

Formula

a(n) = (p^6 - p^3 - p^2 + p)/6, where p = prime(n).
Showing 1-5 of 5 results.