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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A327748 Primes p such that the sum of p and the prime before p is not a multiple of 3.

Original entry on oeis.org

3, 5, 29, 37, 53, 59, 67, 79, 89, 137, 157, 163, 173, 179, 211, 223, 239, 257, 263, 269, 277, 337, 359, 373, 379, 389, 439, 449, 479, 509, 521, 541, 547, 563, 569, 577, 593, 599, 607, 613, 631, 653, 659, 673, 683, 733, 739, 757, 809, 947, 953, 977, 983, 997
Offset: 1

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Author

Todor Szimeonov, Sep 23 2019

Keywords

Comments

Apart from leading terms, similar to A151800(A258578). - Rémy Sigrist, Oct 02 2019
Except for the first two terms (3 and 5), this sequence also represents the primes such that (prime(n)^3 - prime(n-1)^3) is divisible by 3. - Jeff Brown, Jul 06 2020

Examples

			3 is in the sequence because the prime before 3 is 2, and 2 + 3 = 5, and 5 is not divisible by 3.
53 is in the sequence because the prime before 53 is 47, and 47 + 53 = 100, and 100 is not divisible by 3.
		

Crossrefs

Programs

  • Mathematica
    Select[Prime[Range[2,168]],Mod[#+NextPrime[#,-1],3]!=0&] (* Ivan N. Ianakiev, Oct 08 2019 *)
  • PARI
    isok(p) = isprime(p) && (p>2) && ((p+precprime(p-1)) % 3); \\ Michel Marcus, Oct 02 2019
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