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 1-2 of 2 results.

A048152 Triangular array T read by rows: T(n,k) = k^2 mod n, for 1 <= k <= n, n >= 1.

Original entry on oeis.org

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

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Author

Keywords

Examples

			Rows:
  0;
  1, 0;
  1, 1, 0;
  1, 0, 1, 0;
  1, 4, 4, 1, 0;
  1, 4, 3, 4, 1, 0;
		

Crossrefs

Cf. A060036.
Cf. A225126 (central terms).
Cf. A070430 (row 5), A070431 (row 6), A053879 (row 7), A070432 (row 8), A008959 (row 10), A070435 (row 12), A070438 (row 15), A070422 (row 20).
Cf. A046071 (in ascending order, without zeros and duplicates).
Cf. A063987 (for primes, in ascending order, without zeros and duplicates).

Programs

  • Haskell
    a048152 n k = a048152_tabl !! (n-1) !! (k-1)
    a048152_row n = a048152_tabl !! (n-1)
    a048152_tabl = zipWith (map . flip mod) [1..] a133819_tabl
    -- Reinhard Zumkeller, Apr 29 2013
  • Mathematica
    Flatten[Table[PowerMod[k,2,n],{n,15},{k,n}]] (* Harvey P. Dale, Jun 20 2011 *)

Formula

T(n,k) = A133819(n,k) mod n, k = 1..n. - Reinhard Zumkeller, Apr 29 2013
T(n,k) = (T(n,k-1) + (2k+1)) mod n. - Andrés Ventas, Apr 06 2021

A201911 Irregular triangle of 7^k mod prime(n).

Original entry on oeis.org

1, 1, 1, 2, 4, 3, 0, 1, 7, 5, 2, 3, 10, 4, 6, 9, 8, 1, 7, 10, 5, 9, 11, 12, 6, 3, 8, 4, 2, 1, 7, 15, 3, 4, 11, 9, 12, 16, 10, 2, 14, 13, 6, 8, 5, 1, 7, 11, 1, 7, 3, 21, 9, 17, 4, 5, 12, 15, 13, 22, 16, 20, 2, 14, 6, 19, 18, 11, 8, 10, 1, 7, 20, 24, 23, 16, 25
Offset: 1

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Author

T. D. Noe, Dec 07 2011

Keywords

Comments

Except for the fourth row, the first term of each row is 1. Many sequences are in this one: starting at A036132 (mod 71) and A070404 (mod 11).

Examples

			The first 9 rows are:
  1
  1
  1, 2,  4,  3
  0
  1, 7,  5,  2, 3, 10,  4,  6,  9,  8
  1, 7, 10,  5, 9, 11, 12,  6,  3,  8,  4,  2
  1, 7, 15,  3, 4, 11,  9, 12, 16, 10,  2, 14, 13,  6, 8,  5
  1, 7, 11
  1, 7,  3, 21, 9, 17,  4,  5, 12, 15, 13, 22, 16, 20, 2, 14, 6, 19, 18, 11, 8, 10
		

Crossrefs

Cf. A201908 (2^k), A201909 (3^k), A201910 (5^k).
Cf. A070404 (11), A070405 (13), A070407 (17), A070409 (23), A070413 (29), A070415 (31), A070420 (37), A070422 (39), A070424 (41), A070425 (43), A070429 (47), A036132 (71).

Programs

  • GAP
    P:=Filtered([1..350],IsPrime);;
    R:=List([1..Length(P)],n->OrderMod(7,P[n]));;
    Flat(Concatenation([1,1,1,2,4,3,0],List([5..10],n->List([0..R[n]-1],k->PowerMod(7,k,P[n]))))); # Muniru A Asiru, Feb 01 2019
  • Mathematica
    nn = 10; p = 7; t = p^Range[0,Prime[nn]]; Flatten[Table[If[Mod[n, p] == 0, {0}, tm = Mod[t, n]; len = Position[tm, 1, 1, 2][[-1,1]]; Take[tm, len-1]], {n, Prime[Range[nn]]}]]
Showing 1-2 of 2 results.