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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A272284 Numbers n such that 43*n^2 - 537*n + 2971 is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 42, 43, 44, 45, 46, 47, 49, 50, 51, 55, 56, 57, 60, 64, 67, 68, 69, 70, 71, 72, 73, 74, 76, 77, 79, 80, 81
Offset: 1

Views

Author

Robert Price, Apr 24 2016

Keywords

Comments

35 is the smallest number not in this sequence.

Examples

			4 is in this sequence since 43*4^2 - 537*4 + 2971 = 688-2148+2971 = 1511 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0, 100], PrimeQ[43#^2 - 537# + 2971] &]
  • PARI
    lista(nn) = for(n=0, nn, if(ispseudoprime(43*n^2 - 537*n + 2971), print1(n, ", "))); \\ Altug Alkan, Apr 24 2016

A272401 Primes of the form abs(3n^3 - 183n^2 + 3318n - 18757) in order of increasing nonnegative n.

Original entry on oeis.org

18757, 15619, 12829, 10369, 8221, 6367, 4789, 3469, 2389, 1531, 877, 409, 109, 41, 59, 37, 229, 499, 829, 1201, 1597, 1999, 2389, 2749, 3061, 3307, 3469, 3529, 3469, 3271, 2917, 2389, 1669, 739, 419, 1823, 3491, 5441, 7691, 10259, 13163, 16421, 20051, 24071
Offset: 1

Views

Author

Robert Price, Apr 28 2016

Keywords

Examples

			8221 is in this sequence since abs(3*4^3 - 183*4^2 + 3318*4 - 18757) = abs(192-2928+13272-18757) = 8221 is prime.
		

Crossrefs

Programs

  • Mathematica
    n = Range[0, 100]; Select[3n^3 - 183n^2 + 3318n - 18757 , PrimeQ[#] &]

A272118 Numbers k such that abs(6*k^2 - 342*k + 4903) is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 61, 62, 64, 66, 67, 68, 69, 71, 72
Offset: 1

Views

Author

Robert Price, Apr 20 2016

Keywords

Examples

			4 is in this sequence since 6*4^2 - 342*4 + 4903 = 96-1368+4903 = 3631 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0, 100], PrimeQ[6*#^2 - 342*# + 4903] &]
  • PARI
    isok(n) = isprime(abs(6*n^2 - 342*n + 4903)); \\ Michel Marcus, Apr 21 2016

A272302 Nonnegative numbers n such that abs(3n^3 - 183n^2 + 3318n - 18757) is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 48, 49, 51, 53, 56, 57, 59, 60, 62, 63, 65, 66, 69, 70, 74, 79, 80, 81, 82, 85
Offset: 1

Views

Author

Robert Price, Apr 28 2016

Keywords

Comments

47 is the smallest number not in this sequence.

Examples

			4 is in this sequence since abs(3*4^3 - 183*4^2 + 3318*4 - 18757) = abs(192-2928+13272-18757) = 8221 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0, 100], PrimeQ[3#^3 - 183#^2 + 3318# - 18757 ] &]
  • PARI
    is(n)=isprime(abs(3*n^2-183*n^2+3318*n-18757)) \\ Charles R Greathouse IV, Feb 17 2017

A272438 Primes of the form abs(-66n^3 + 3845n^2 - 60897n + 251831) in order of increasing nonnegative n.

Original entry on oeis.org

251831, 194713, 144889, 101963, 65539, 35221, 10613, 8681, 23057, 32911, 38639, 40637, 39301, 35027, 28211, 19249, 8537, 3529, 16553, 30139, 43891, 57413, 70309, 82183, 92639, 101281, 107713, 111539, 112363, 109789, 103421, 92863, 77719, 57593, 32089, 811
Offset: 1

Views

Author

Robert Price, Apr 29 2016

Keywords

Examples

			65539 is in this sequence since abs(-66*4^3 + 3845*4^2 - 60897*4 + 251831) = abs(-4224+61520-243588+251831) = 65539 is prime.
		

Crossrefs

Programs

  • Mathematica
    n = Range[0, 100]; Select[-66n^3 + 3845n^2 - 60897n + 251831, PrimeQ[#] &]

A272437 Nonnegative numbers n such that abs(-66n^3 + 3845n^2 - 60897n + 251831) is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 47, 49, 51, 54, 58, 65, 68, 70, 75, 76, 77, 82, 88, 89, 97, 99, 101, 102, 104, 109
Offset: 1

Views

Author

Robert Price, Apr 29 2016

Keywords

Comments

46 is the smallest number not in this sequence.

Examples

			4 is in this sequence since abs(-66*4^3 + 3845*4^2 - 60897*4 + 251831) = abs(-4224+61520-243588+251831) = 65539 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0, 109], PrimeQ[-66#^3 + 3845#^2 - 60897# + 251831] &]
  • PARI
    is(n)=isprime(abs(66*n^3-3845*n^2+60897*n-251831)) \\ Charles R Greathouse IV, Feb 20 2017

A272444 Primes of the form abs(n^5 - 99n^4 + 3588n^3 - 56822n^2 + 348272n - 286397) in order of increasing nonnegative n.

Original entry on oeis.org

286397, 8543, 210011, 336121, 402851, 424163, 412123, 377021, 327491, 270631, 212123, 156353, 106531, 64811, 32411, 9733, 3517, 8209, 5669, 2441, 14243, 27763, 41051, 52301, 59971, 62903, 60443, 52561, 39971, 24251, 7963, 5227, 10429, 1409, 29531, 91673
Offset: 1

Views

Author

Robert Price, Apr 29 2016

Keywords

Examples

			402851 is in this sequence since abs(4^5 - 99*4^4 + 3588*4^3 - 56822*4^2 + 348272*4 - 286397) = abs(1024-25344+229632-909152+1393088-286397) = 402851 is prime.
		

Crossrefs

Programs

  • Mathematica
    n = Range[0, 100]; Select[n^5 - 99n^4 + 3588n^3 - 56822n^2 + 348272n - 286397, PrimeQ[#] &]
  • PARI
    lista(nn) = for(n=0, nn, if(isprime(p=abs(n^5-99*n^4+3588*n^3-56822*n^2+348272*n-286397)), print1(p, ", "))); \\ Altug Alkan, Apr 29 2016

A117081 a(n) = 36*n^2 - 810*n + 2753, producing the conjectured record number of 45 primes in a contiguous range of n for quadratic polynomials, i.e., abs(a(n)) is prime for 0 <= n < 44.

Original entry on oeis.org

2753, 1979, 1277, 647, 89, -397, -811, -1153, -1423, -1621, -1747, -1801, -1783, -1693, -1531, -1297, -991, -613, -163, 359, 953, 1619, 2357, 3167, 4049, 5003, 6029, 7127, 8297, 9539, 10853, 12239, 13697, 15227, 16829, 18503, 20249, 22067, 23957, 25919, 27953, 30059, 32237, 34487, 36809, 39203, 41669
Offset: 0

Views

Author

Roger L. Bagula, Apr 17 2006

Keywords

Comments

The absolute values of a(n) for 0 <= n <= 44 are primes, a(45) = 39203 = 197*199. The positive prime terms are in A050268.
The polynomial is a transformed version of the polynomial P(x) = 36*x^2 + 18*x - 1801 whose absolute value gives 45 distinct primes for -33 <= x <= 11, found by Ruby in 1989. It is one of the 3 known quadratic polynomials whose absolute value produces more than 40 primes in a contiguous range from 0 to n. For the other two polynomials, which produce 43 primes, see A050267 and A267252. - Hugo Pfoertner, Dec 13 2019

References

  • Paulo Ribenboim, The Little Book of Bigger Primes, Second Edition, Springer-Verlag New York, 2004. See p. 147.

Crossrefs

Programs

  • Magma
    I:=[2753, 1979, 1277]; [n le 3 select I[n] else 3*Self(n-1)-3 *Self(n-2)+Self(n-3): n in [1..50]]; // Vincenzo Librandi, May 12 2012
  • Mathematica
    f[n_] := If[Mod[n, 2] == 1, 36*n^2 - 810*n + 2753, 36*n^2 - 810*n + 2753] a = Table[f[n], {n, 0, 100}]
    CoefficientList[Series[(2753-6280*x+3599*x^2)/(1-x)^3,{x,0,50}],x] (* Vincenzo Librandi, May 12 2012 *)
    Table[36n^2-810n+2753,{n,0,50}] (* or *) LinearRecurrence[{3,-3,1},{2753,1979,1277},50] (* Harvey P. Dale, Jun 20 2013 *)
  • PARI
    {for(n=0, 46, print1(36*n^2-810*n+2753, ","))}
    

Formula

G.f.: (2753 - 6280*x + 3599*x^2)/(1-x)^3. - Colin Barker, May 10 2012
a(0)=2753, a(1)=1979, a(2)=1277, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Harvey P. Dale, Jun 20 2013
E.g.f.: exp(x)*(2753 - 774*x + 36*x^2). - Elmo R. Oliveira, Feb 09 2025

Extensions

Edited by N. J. A. Sloane, Apr 27 2007
Title extended by Hugo Pfoertner, Dec 13 2019

A256585 Primes of the form 3n^2 + 39n + 37.

Original entry on oeis.org

37, 79, 127, 181, 241, 307, 379, 457, 541, 631, 727, 829, 937, 1051, 1171, 1297, 1429, 1567, 1861, 2017, 2179, 2347, 2521, 2887, 3079, 3691, 3907, 4129, 4357, 4591, 4831, 5077, 5851, 6121, 6397, 6679, 6967, 7561, 7867, 8179, 8821, 9151, 9829, 10177, 10531
Offset: 1

Views

Author

S. J. Vincent, Apr 02 2015

Keywords

Comments

Primes of the form 6*m+1 such that 8*m + 121 is a square. - Bruno Berselli, Apr 18 2016

Crossrefs

Programs

  • Maple
    select(isprime, [3*k*(k+13)+37$k=0..100])[];  # Alois P. Heinz, Apr 16 2025
  • Mathematica
    Select[(3 #^2 + 39 # + 37) & /@ Range[0, 100], PrimeQ] (* Robert Price, Apr 16 2025 *)

A272323 Nonnegative numbers n such that abs(82n^3 - 1228n^2 + 6130n - 5861) is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 34, 37, 39, 41, 43, 47, 49, 50, 53, 54, 55, 59, 61, 63, 64, 67, 72, 73, 75, 76, 81, 84, 86, 87, 88, 89, 90, 92, 95, 97, 98, 102, 103, 104
Offset: 1

Views

Author

Robert Price, Apr 25 2016

Keywords

Comments

32 is the smallest number not in this sequence.

Examples

			4 is in this sequence since 82*4^3 - 1228*4^2 + 6130*4 - 5861 = 5248-19648+24520-5861 = 4259 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0, 100], PrimeQ[82#^3 - 1228#^2 + 6130# - 5861] &]
  • PARI
    lista(nn) = for(n=0, nn, if(isprime(abs(82*n^3-1228*n^2+6130*n-5861)), print1(n, ", "))); \\ Altug Alkan, Apr 25 2016
Previous Showing 11-20 of 47 results. Next