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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A143153 Triangle read by rows, A054525 * (A020639 * 0^(n-k)), 1<=k<=n.

Original entry on oeis.org

1, -1, 2, -1, 0, 3, 0, -2, 0, 2, -1, 0, 0, 0, 5, 1, -2, -3, 0, 0, 2, -1, 0, 0, 0, 0, 0, 7, 0, 0, 0, -2, 0, 0, 0, 2, 0, 0, -3, 0, 0, 0, 0, 0, 3, 1, -2, 0, 0, -5, 0, 0, 0, 0, 2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 0, 2, 0, -2, 0, -2, 0, 0, 0, 0, 0, 2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13, 1, -2, 0, 0, 0, 0, -7, 0, 0, 0, 0, 0, 0, 2
Offset: 1

Views

Author

Gary W. Adamson & Mats Granvik, Jul 27 2008

Keywords

Comments

Right border = A020639, Lpf(n): (1, 2, 3, 2, 5, 2, 7, 2, 3, 2, 11,...).
Left border = mu(n), A008683: (1, -1, -1, 0, -1, 1, -1,...).
Row sums = a signed version of A097945: (1, -1, -2, 0, -4, 2, -6,...) such that parity = (+) iff mu(n) = +.

Examples

			First few rows of the triangle =
1;
-1, 2;
-1, 0, 3;
0, -2, 0, 2;
-1, 0, 0, 0, 5;
1, -2, -3, 0, 0, 2;
-1, 0, 0, 0, 0, 0, 7;
0, 0, 0, -2, 0, 0, 0, 2;
0, 0, -3, 0, 0, 0, 0, 0, 3;
1, -2, 0, 0, -5, 0, 0, 0, 0, 2;
-1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11;
0, 2, 0, -2, 0, -2, 0, 0, 0, 0, 0, 2;
...
		

Crossrefs

Formula

Triangle read by rows, A054525 * (A020639 * 0^(n-k)), 1<=k<=n; where A020639 = Lpf(n): (1, 2, 3, 2, 5, 2, 7, 2, 3, 2,...) and A054525 = the Mobius transform.

A143258 Triangle read by rows, A054525 * A143257, 1<=k<=n.

Original entry on oeis.org

1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 4, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 6, 1, 1, 1, 1, 1, 1, 4, 2, 1, 1, 1, 1, 1, 1, 6, 2, 2, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 3, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 6, 6, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 1

Views

Author

Gary W. Adamson, Aug 02 2008

Keywords

Comments

Left border = phi(n), A000010.
Row sums = A029935: (1, 2, 4, 5, 8, 8, 12, 12,...)

Examples

			First few rows of the triangle =
1;
1, 1;
2, 1, 1;
2, 1, 1, 1;
4, 1, 1, 1, 1;
2, 2, 1, 1, 1, 1;
6, 1, 1, 1, 1, 1, 1;
...
		

Crossrefs

Formula

Mobius transform of triangle A143257

A143275 A054525 * A029935.

Original entry on oeis.org

1, 1, 3, 3, 7, 3, 11, 7, 12, 7, 19, 9, 23, 11, 21, 16, 31, 12, 35, 21, 33, 19, 43, 21, 48, 23, 44, 33, 55, 21, 59, 36, 57, 31, 77, 36, 71, 35, 69, 49, 79, 33, 83, 57, 84, 43, 91, 48, 108, 48, 93, 69, 103, 44, 133, 77, 105, 55, 115, 63, 119, 59, 132, 80, 161, 57, 131, 93, 129
Offset: 1

Views

Author

Gary W. Adamson, Aug 03 2008

Keywords

Examples

			a(4) = 3 = (0, -1, 0, 1) dot (1, 2, 4, 5) = (0 - 2 + 0 + 5), where K(0, -1, 0, 1) = row 4 of A054525 and A143275 = (1, 2, 4, 5, 8, 8, 12, ...).
		

Crossrefs

Programs

  • Maple
    read("transforms") : A029935 := proc(n) local a,d ; a := 0 ; for d in numtheory[divisors](n) do a := a+ numtheory[phi](d)*numtheory[phi](n/d); od; RETURN(a) ; end: a029935 := [seq(A029935(n),n=1..300)] ; a143275 := MOBIUS(a029935) ; # R. J. Mathar, Jan 19 2009
  • Mathematica
    f[p_, e_] := If[e > 1, (e*(p-1) + p + 2) * (p-1)^2 * p^(e-3), 2*p - 3]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Aug 31 2023 *)

Formula

Möbius transform (A054525) of A029935: (1, 2, 4, 5, 8, 8, 12, 12, 16, ...).
Multiplicative with a(p) = 2*p - 3 and a(p^e) = (e*(p-1) + p + 2) * (p-1)^2 * p^(e-3) for e > 1. - Amiram Eldar, Aug 31 2023

Extensions

More terms from R. J. Mathar, Jan 19 2009

A143276 Triangle read by rows: A054525 * A054523 as infinite lower triangular matrices.

Original entry on oeis.org

1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 3, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 5, 0, 0, 0, 0, 0, 1, 2, 1, 0, 0, 0, 0, 0, 1, 4, 0, 1, 0, 0, 0, 0, 0, 1, 0, 3, 0, 0, 0, 0, 0, 0, 0, 1, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
Offset: 1

Views

Author

Gary W. Adamson, Aug 03 2008

Keywords

Comments

Row sums = phi(n), A000010: (1, 1, 2, 2, 4, 2, 6,...).
Left border = A007431: (1, 0, 1, 1, 3, 0, 5, 2, 4,...).

Examples

			First few rows of the triangle =
1;
0, 1;
1, 0, 1;
1, 0, 0, 1;
3, 0, 0, 0, 1;
0, 1, 0, 0, 0, 1;
5, 0, 0, 0, 0, 0, 1;
2, 1, 0, 0, 0, 0, 0, 1;
...
		

Crossrefs

Formula

Moebius transform of triangle A054523.

Extensions

a(17), a(18) corrected by Georg Fischer, May 29 2023

A143309 Triangle read by rows, A054525 * A143308, 1<=k<=n.

Original entry on oeis.org

1, 3, 2, 5, 3, 3, 8, 6, 4, 4, 9, 5, 5, 5, 5, 15, 13, 9, 6, 6, 6, 13, 7, 7, 7, 7, 7, 7, 20, 16, 12, 12, 8, 8, 8, 8, 21, 15, 15, 9, 9, 9, 9, 9, 9, 27, 23, 15, 15, 15, 10, 10, 10, 10, 10, 21, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 40, 36, 32, 26, 18, 18, 12, 12, 12, 12, 12, 12, 25, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13
Offset: 1

Views

Author

Gary W. Adamson, Aug 06 2008

Keywords

Comments

Row sums = A069097: (1, 5, 11, 22, 29, 55,...).
Left border = A018804: (1, 3, 5, 8, 9, 15,...).

Examples

			First few rows of the triangle =
1;
3, 2;
5, 3, 3;
8, 6, 4, 4;
9, 5, 5, 5, 5;
15, 13, 9, 6, 6, 6;
13, 7, 7, 7, 7, 7, 7;
...
		

Crossrefs

Formula

Mobius transform of triangle A143308.

Extensions

a(56) = 10 removed and more terms from Georg Fischer, Jul 13 2023

A143312 Triangle read by rows, A054525 * A143311, 1<=k<=n.

Original entry on oeis.org

1, 3, 2, 8, 0, 3, 12, 6, 0, 4, 24, 0, 0, 0, 5, 24, 16, 9, 0, 0, 6, 48, 0, 0, 0, 0, 0, 7, 48, 24, 0, 12, 0, 0, 0, 8, 72, 0, 24, 0, 0, 0, 0, 0, 9, 72, 48, 0, 0, 15, 0, 0, 0, 0, 10, 120, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 96, 48, 36, 32, 0, 18, 0, 0, 0, 0, 0, 12, 168, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13
Offset: 1

Views

Author

Gary W. Adamson, Aug 06 2008

Keywords

Comments

Left border = A007434.
Row sums = A069097: (1, 5, 11, 2, 29, 55,...)

Examples

			First few rows of the triangle =
1;
3, 2;
8, 0, 3;
12, 6, 0, 4;
24, 0, 0, 0, 5;
24, 16, 9, 0, 0, 6;
48, 0, 0, 0, 0, 0, 7;
48, 24, 0, 12, 0, 0, 0, 8;
...
		

Crossrefs

Formula

Mobius transform of triangle A143311

A143316 Triangle read by rows, A054525 * A143315, 1<=k<=n.

Original entry on oeis.org

1, 2, 1, 4, 0, 1, 4, 2, 0, 1, 8, 0, 0, 0, 1, 4, 4, 2, 0, 0, 1, 12, 0, 0, 0, 0, 0, 1, 8, 4, 0, 2, 0, 0, 0, 1, 12, 0, 4, 0, 0, 0, 0, 0, 1, 8, 8, 0, 0, 2, 0, 0, 0, 0, 1, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 8, 4, 4, 4, 0, 2, 0, 0, 0, 0, 0, 1, 24, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 12, 12, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 1
Offset: 1

Views

Author

Gary W. Adamson, Aug 06 2008

Keywords

Comments

Row sums = 2*n-1.
Left border = A140434: (1, 2, 4, 4, 8, 4, 12, 8,...).

Examples

			First few rows of the triangle =
1;
2, 1;
4, 0, 1;
4, 2, 0, 1;
8, 0, 0, 0, 1;
4, 4, 2, 0, 0, 1;
12, 0, 0, 0, 0, 0, 1;
8, 4, 0, 2, 0, 0, 0, 1;
...
		

Crossrefs

Extensions

a(19) corrected and more terms from Georg Fischer, Aug 14 2023

A143444 A054525 * the primes prefaced by 0.

Original entry on oeis.org

0, 2, 3, 3, 7, 6, 13, 12, 16, 14, 29, 17, 37, 26, 33, 30, 53, 32, 61, 41, 55, 42, 79, 40, 82, 58, 82, 59, 107, 44, 113, 80, 99, 82, 119, 70, 151, 94, 123, 88, 173, 74, 181, 115, 134, 116, 199, 98, 210, 122, 173, 133, 239, 100, 215, 142, 199, 160, 271, 107, 281, 168, 206
Offset: 1

Views

Author

Gary W. Adamson, Aug 15 2008

Keywords

Comments

a(5) = 7 = (-1, 0, 0, 0, 1) dot (0, 2, 3, 5, 7).
a(p(n)) = p(n-1) since prime rows of the Mobius transform have only one nonzero multiplier besides the (-1) which is multiplied * the 0 in (0, 2, 3, 5, 7,...). Cf. A055003: (1, 3, 7, 13, 29, 37,...) a subset of primes in the sequences, but other terms may be primes.

Examples

			a(6) = 6 = (1, -1, -1, 0, 0, 1) dot (0, 2, 3, 5, 7, 11) where (1, -1, -1, 0, 0, 1) = row 6 of A051731, the Mobius transform.
		

Crossrefs

Formula

Mobius transform of the primes prefaced by 0.

Extensions

a(12) replaced by 17 and extended by R. J. Mathar, Jan 19 2009

A143517 Triangle read by rows, A054525 * (A061397 * 0^(n-k)), 1<=k<=n.

Original entry on oeis.org

0, 0, 2, 0, 0, 3, 0, -2, 0, 0, 0, 0, 0, 0, 5, 0, -2, -3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -3, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13
Offset: 1

Views

Author

Gary W. Adamson, Aug 22 2008

Keywords

Comments

Row sums = A137851: (0, 2, 3, -2, 5, -5, 7, 0, -3,...).
Right border = A061397: (0, 2, 3, 0, 5, 0, 7,...).

Examples

			First few rows of the triangle =
0;
0, 2;
0, 0, 3;
0, -2, 0, 0;
0, 0, 0, 0, 5;
0, -2, -3, 0, 0, 0;
0, 0, 0, 0, 0, 0, 7;
...
		

Crossrefs

Formula

Triangle read by rows, A054525 * (A061397 * 0^(n-k)), 1<=k<=n

A143518 Triangle read by rows, A054525 * (A010051 * 0^(n-k)), 1<=k<=n.

Original entry on oeis.org

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

Views

Author

Gary W. Adamson, Aug 22 2008

Keywords

Comments

Row sums = A143519: (0, 1, 1, -1, 1, -2, 1, 0, -1,...)

Examples

			First few rows of the triangle =
0;
0, 1;
0, 0, 1;
0, -1, 0, 0;
0, 0, 0, 0, 1;
0, -1, -1, 0, 0, 0;
0, 0, 0, 0, 0, 0, 1;
...
		

Crossrefs

Formula

Triangle read by rows, A054525 * A010051, 1<=k<=n. A054525 = the Mobius transform. A010051 * 0^(n-k) = an infinite lower triangular matrix with A010051, the characteristic function of the primes (0, 1, 1, 0, 1, 0, 1,...) as the main diagonal and the rest zeros.
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