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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.

User: Christopher A. Curry

Christopher A. Curry's wiki page.

Christopher A. Curry has authored 1 sequences.

A357270 a(n) = s(n) mod prime(n+1), where s = A143293.

Original entry on oeis.org

1, 0, 4, 4, 7, 11, 0, 3, 15, 6, 11, 9, 4, 41, 4, 26, 28, 56, 4, 54, 23, 37, 78, 48, 11, 17, 32, 68, 85, 34, 78, 12, 120, 28, 68, 24, 76, 116, 17, 55, 40, 3, 91, 111, 132, 133, 195, 75, 179, 44, 211, 108, 3, 63, 21, 28, 85, 22, 208, 237, 9, 166, 81, 183, 205, 208
Offset: 0

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Author

Christopher A. Curry, Sep 21 2022

Keywords

Comments

Let i be some positive integer. Let r(n) = i mod prime(n+1). Let m be defined such that s(m-1) <= i < s(m). Then the first m values in the sequence {r(n)} uniquely define the integer (it is the least positive integer requiring those m remainders modulo those primes). If i is a term of {s(n)}, then a(n) = r(n) for n = 0..m-1.

Links

Crossrefs

Cf. A000040, A143293.

Programs

  • Mathematica
    q[n_] := Insert[Table[Mod[Total[Table[Product[Prime[i], {i, 1, r}], {r, m}]] + 1, Prime[m + 1]], {m, n}], 1, 1]; q[65] (* Samuel Harkness, Sep 22 2022 *)
  • PARI
    a(n) = if(n==0, return(1)); my(P=1, s=1); forprime(p=2, prime(n), s+=P*=p); s % prime(n+1); \\ Michel Marcus, Sep 22 2022
  • PARI
    a(n,q=prime(n+1))=my(P=Mod(1,q),s=P); forprime(p=2,q-1, s+=P*=p); lift(s) \\ Charles R Greathouse IV, Sep 22 2022

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