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 1-3 of 3 results.

A144619 a(n) = 19*n + 8.

Original entry on oeis.org

8, 27, 46, 65, 84, 103, 122, 141, 160, 179, 198, 217, 236, 255, 274, 293, 312, 331, 350, 369, 388, 407, 426, 445, 464, 483, 502, 521, 540, 559, 578, 597, 616, 635, 654, 673, 692, 711, 730, 749, 768, 787, 806, 825, 844, 863, 882, 901, 920, 939, 958, 977, 996
Offset: 0

Views

Author

Vincenzo Librandi, Jan 15 2009

Keywords

Crossrefs

Programs

Formula

From Vincenzo Librandi, May 14 2012: (Start)
G.f.: (11*x+8)/(1-x)^2.
a(n) = 2*a(n-1) - a(n-2). (End)
E.g.f.: exp(x)*(8 + 19*x). - Elmo R. Oliveira, Apr 04 2025

Extensions

Offset corrected by Jon E. Schoenfield, Jun 17 2010

A144620 Numbers k such that k and 19*k + 8 are both prime.

Original entry on oeis.org

5, 17, 41, 59, 89, 167, 191, 239, 269, 281, 359, 449, 479, 491, 509, 521, 587, 617, 647, 701, 719, 821, 881, 911, 929, 971, 1031, 1181, 1217, 1259, 1289, 1307, 1361, 1367, 1559, 1601, 1697, 1709, 1721, 1787, 1877, 1889, 1907, 1931, 1949, 1997, 2039, 2129
Offset: 1

Views

Author

Vincenzo Librandi, Jan 15 2009

Keywords

Examples

			For n=5, 19*5 + 8 = 103;
for n=269, 19*269 + 8 = 5119.
		

Crossrefs

Programs

  • Magma
    [p: p in PrimesUpTo(2500)|IsPrime(19*p+8)] // Vincenzo Librandi, Aug 30 2012
  • Maple
    a := proc (n) if isprime(n) = true and isprime(19*n+8) = true then n else end if end proc: seq(a(n), n = 1 .. 2300); # Emeric Deutsch, Jan 27 2009
  • Mathematica
    Select[Prime[Range[400]], PrimeQ[#] &&PrimeQ[19#+8] &] (* Vincenzo Librandi, Aug 30 2012 *)

Extensions

Extended by Emeric Deutsch, Jan 27 2009

A274202 Primes congruent to 31 mod 65.

Original entry on oeis.org

31, 421, 811, 941, 1201, 1721, 2111, 2371, 3541, 3671, 3931, 4451, 5101, 5231, 5881, 6011, 6271, 6661, 6791, 8221, 8741, 9001, 9391, 9521, 9781, 10301, 10691, 11471, 11731, 12251, 12511, 12641, 13291, 13421, 13681, 14071, 14461, 14591, 14851, 15241, 15761
Offset: 1

Views

Author

Vincenzo Librandi, Jun 13 2016

Keywords

Comments

Subsequence of A030430 and A102732.

Crossrefs

Cf. similar sequences of the type primes congruent to k mod 2*k+3: A045392 (k=2), A102732 (k=5), A138629 (k=7), A141873 (k=8), A141914 (k=10), A141935 (k=11), A141989 (k=13), A142018 (k=14), A142086 (k=16), A142126 (k=17), A142216 (k=19), A142269 (k=20), A142373 (k=22), A142433 (k=23), A142555 (k=25), A142619 (k=26), A142755 (k=28), A142827 (k=29), this sequence (k=31), A154621 (k=32), A154624 (k=34), A154628 (k=35).

Programs

  • Magma
    [p: p in PrimesUpTo(20000) | p mod 65 eq 31];
  • Mathematica
    Select[Prime[Range[2000]], MemberQ[{31}, Mod[#, 65]] &]
    Select[Range[31,16000,65],PrimeQ] (* Harvey P. Dale, May 06 2018 *)
Showing 1-3 of 3 results.