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.

Previous Showing 11-16 of 16 results.

A165579 Partial sums of A011628.

Original entry on oeis.org

0, 1, 2, 1, 2, 1, 0, 1, 2, 3, 2, 1, 0, 1, 2, 3, 4, 3, 4, 5, 4, 3, 2, 3, 2, 3, 4, 3, 4, 5, 6, 7, 8, 9, 8, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 3, 4, 3, 2, 3, 4, 5, 6, 5, 4, 5, 6, 5, 6, 5, 6, 5, 6, 7, 8, 7, 8, 7, 6, 5, 4, 5, 6, 5, 6, 5, 6, 5, 4, 3, 2, 3, 2, 1, 0, 1, 0, -1, -2, -1, -2, -1, 0, -1, -2, -3, -4
Offset: 0

Views

Author

Antti Karttunen, Sep 22 2009

Keywords

Comments

Period 233.

Crossrefs

Programs

  • Mathematica
    Table[ JacobiSymbol[n, 233], {n, 0, 96}] // Accumulate (* Jean-François Alcover, Oct 08 2013 *)

A226518 Irregular triangle read by rows: T(n,k) = Sum_{i=0..k} Legendre(i,prime(n)).

Original entry on oeis.org

0, 1, 0, 1, 0, 0, 1, 0, -1, 0, 0, 1, 2, 1, 2, 1, 0, 0, 1, 0, 1, 2, 3, 2, 1, 0, 1, 0, 0, 1, 0, 1, 2, 1, 0, -1, -2, -1, 0, -1, 0, 0, 1, 2, 1, 2, 1, 0, -1, 0, 1, 0, -1, -2, -1, -2, -1, 0, 0, 1, 0, -1, 0, 1, 2, 3, 2, 3, 2, 3, 2, 1, 0, -1, 0, 1, 0, 0, 1, 2, 3, 4, 3, 4, 3, 4, 5, 4, 3, 4, 5, 4, 3, 4, 3, 4, 3, 2, 1, 0
Offset: 1

Views

Author

N. J. A. Sloane, Jun 19 2013

Keywords

Comments

Strictly speaking, the symbol in the definition is the Legendre-Jacobi-Kronecker symbol, since the Legendre symbol is defined only for odd primes.
The classical Polya-Vinogradov theorem gives an upper bound.
There is a famous open problem concerning upper bounds on |T(n,k)| for small k.

Examples

			Triangle begins:
  0, 1;
  0, 1, 0;
  0, 1, 0, -1, 0;
  0, 1, 2,  1, 2, 1, 0;
  0, 1, 0,  1, 2, 3, 2,  1,  0,  1, 0;
  0, 1, 0,  1, 2, 1, 0, -1, -2, -1, 0, -1,  0;
  0, 1, 2,  1, 2, 1, 0, -1,  0,  1, 0, -1, -2, -1, -2, -1, 0;
  0, 1, 0, -1, 0, 1, 2,  3,  2,  3, 2,  3,  2,  1,  0, -1, 0, 1, 0;
  ...
		

References

  • R. Ayoub, An Introduction to the Analytic Theory of Numbers, Amer. Math. Soc., 1963; p. 320, Theorem 5.1.
  • Beck, József. Inevitable randomness in discrete mathematics. University Lecture Series, 49. American Mathematical Society, Providence, RI, 2009. xii+250 pp. ISBN: 978-0-8218-4756-5; MR2543141 (2010m:60026). See page 23.
  • Elliott, P. D. T. A. Probabilistic number theory. I. Mean-value theorems. Grundlehren der Mathematischen Wissenschaften, 239. Springer-Verlag, New York-Berlin, 1979. xxii+359+xxxiii pp. (2 plates). ISBN: 0-387-90437-9 MR0551361 (82h:10002a). See Vol. 1, p. 154.

Crossrefs

Partial sums of rows of triangle in A226520.
See A226519 for another version.
Third and fourth columns give A226914, A226915.
See also A226523.
Cf. A165477 (131071st row), A165582.

Programs

  • Haskell
    a226518 n k = a226518_tabf !! (n-1) !! k
    a226518_row n = a226518_tabf !! (n-1)
    a226518_tabf = map (scanl1 (+)) a226520_tabf
    -- Reinhard Zumkeller, Feb 02 2014
    
  • Magma
    A226518:= func< n,k | n eq 1 select k else  (&+[JacobiSymbol(j, NthPrime(n)): j in [0..k]]) >;
    [A226518(n,k) : k in [0..NthPrime(n)-1], n in [1..15]]; // G. C. Greubel, Oct 05 2024
    
  • Maple
    with(numtheory);
    T:=(n,k)->add(legendre(i,ithprime(n)),i=0..k);
    f:=n->[seq(T(n,k),k=0..ithprime(n)-1)];
    [seq(f(n),n=1..15)];
  • Mathematica
    Table[p = Prime[n]; Table[JacobiSymbol[k, p], {k, 0, p-1}] // Accumulate, {n, 1, 15}] // Flatten (* Jean-François Alcover, Mar 07 2014 *)
  • PARI
    print("# A226518 ");
    cnt=1; for(j5=1,9,summ=0; for(i5=0,prime(j5)-1, summ=summ+kronecker(i5,prime(j5)); print(cnt,"  ",summ); cnt++)); \\ Bill McEachen, Aug 02 2013
    
  • SageMath
    def A226518(n,k): return k if n==1 else sum(jacobi_symbol(j, nth_prime(n)) for j in range(k+1))
    flatten([[A226518(n,k) for k in range(nth_prime(n))] for n in range(1,16)]) # G. C. Greubel, Oct 05 2024

A165576 Partial sums of A165574.

Original entry on oeis.org

0, 1, 2, 3, 4, 3, 4, 3, 4, 5, 4, 5, 6, 7, 6, 5, 6, 7, 8, 7, 6, 5, 6, 7, 8, 9, 10, 11, 10, 9, 8, 9, 10, 11, 12, 13, 14, 15, 14, 15, 14, 13, 12, 13, 14, 13, 14, 13, 14, 15, 16, 17, 18, 17, 18, 17, 16, 15, 14, 13, 12, 13, 14, 13, 14, 13, 14, 13, 14, 15, 16, 15, 16, 15, 16, 17, 16, 15
Offset: 0

Views

Author

Antti Karttunen, Sep 22 2009

Keywords

Comments

Period 263. There are no negative values as 263 is one of the primes in A095102.

Crossrefs

Programs

  • Mathematica
    Accumulate[JacobiSymbol[Range[0,90],263]] (* Harvey P. Dale, Sep 01 2021 *)

A165476 Legendre symbol (n,131071).

Original entry on oeis.org

0, 1, 1, -1, 1, 1, -1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, 1, 1, -1, 1, 1, 1, -1, -1, 1, 1, -1, -1, 1, 1, 1, 1, 1, -1, 1, 1, -1, -1, -1, -1, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, -1, 1, -1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, 1, 1, -1, 1, -1, 1
Offset: 0

Views

Author

Antti Karttunen, Sep 21 2009

Keywords

Comments

131071 is the 6th Mersenne prime, A000668(6).
See row 12251 in triangle A226520, A000040(12251) = 131071. - Reinhard Zumkeller, Feb 02 2014

Crossrefs

Partial sums: A165477.
Cf. A097343.

Programs

  • Haskell
    a165476 = flip legendreSymbol 131071
    -- Where the function legendreSymbol is defined in A097343.
    -- Reinhard Zumkeller, Feb 02 2014
  • Mathematica
    a[n_] := JacobiSymbol[n, 2^17 - 1];
    Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Jan 13 2023 *)

A165578 Partial sums of A011627.

Original entry on oeis.org

0, 1, 0, 1, 2, 3, 2, 1, 0, 1, 0, 1, 2, 1, 2, 3, 4, 5, 4, 5, 6, 5, 4, 3, 2, 3, 4, 5, 4, 3, 2, 1, 0, 1, 0, -1, 0, 1, 0, -1, -2, -3, -2, -1, 0, 1, 2, 1, 2, 3, 2, 3, 2, 3, 2, 3, 4, 5, 6, 5, 6, 7, 8, 7, 8, 7, 6, 5, 6, 5, 6, 7, 6, 5, 4, 5, 6, 5, 6, 5, 6, 7, 8, 9, 8, 9, 8, 7, 6, 5, 4, 5, 4, 3, 4, 5, 4, 5, 4
Offset: 0

Views

Author

Antti Karttunen, Sep 22 2009

Keywords

Comments

Period 229.

Crossrefs

Programs

Formula

a(n) = -(a(n-1) + a(n-2) + ... + a(n-228)) = a(n-229). - Charles R Greathouse IV, Feb 11 2013

A165577 Partial sums of A011626.

Original entry on oeis.org

0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 3, 4, 3, 2, 1, 2, 1, 0, 1, 0, 1, 0, 1, 0, 1, 2, 3, 4, 5, 6, 5, 4, 5, 6, 5, 6, 5, 4, 3, 4, 3, 2, 3, 4, 3, 2, 3, 4, 5, 4, 3, 2, 3, 2, 1, 0, 1, 0, 1, 0, -1, 0, 1, 2, 3, 2, 1, 0, 1, 2, 3, 2, 3, 4, 5, 6, 7, 8, 9, 8, 9, 10, 9, 10, 11, 10, 11, 10, 11, 12, 11, 12, 11, 10, 9
Offset: 0

Views

Author

Antti Karttunen, Sep 22 2009

Keywords

Comments

Period 227.

Crossrefs

Previous Showing 11-16 of 16 results.