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 1-6 of 6 results.

A095169 Leading diagonal of the triangle A095167.

Original entry on oeis.org

1, 4, 9, 14, 30, 26, 63, 48, 66, 72, 176, 90, 247, 119, 144, 168, 425, 198, 551, 230, 270, 290, 828, 327, 445, 394, 474, 470, 1305, 519, 1426, 592, 636, 680, 749, 756, 2072, 838, 903, 926, 2624, 978, 2881, 1058, 1130, 1194, 3337, 1266, 1582, 1356
Offset: 1

Views

Author

Amarnath Murthy, Jun 01 2004

Keywords

Crossrefs

Programs

  • PARI
    S=Set(); for(n=2,20, k=0; m=1; while(k1, S=setunion(S,[m]); k++) ); print1(" ",m) ) (Alekseyev)

Extensions

More terms from Max Alekseyev, Jun 30 2005

A095170 Row sums of A095167.

Original entry on oeis.org

1, 6, 18, 44, 95, 127, 280, 318, 432, 616, 1276, 962, 2067, 1480, 1820, 2360, 4709, 3258, 6802, 4105, 4943, 5818, 12719, 7345, 9235, 9398, 11373, 11675, 25201, 14899, 28458, 17828, 18882, 21879, 23246, 25703, 50283, 30272, 31983, 35175, 71668
Offset: 1

Views

Author

Amarnath Murthy, Jun 01 2004

Keywords

Crossrefs

Programs

  • PARI
    S=Set();for(n=2,50,k=0;m=1;s=0;while(k1,S=setunion(S,[m]);k++;s+=m));print1(" ",s)) (Alekseyev)

Extensions

More terms from Max Alekseyev, Jun 30 2005

A095171 Number of multiples of n in the n-th row of the triangle A095167.

Original entry on oeis.org

1, 2, 3, 2, 5, 2, 7, 3, 3, 2, 11, 1, 13, 2, 2, 2, 17, 2, 19, 2, 2, 2, 23, 1, 4, 2, 2, 1, 29, 2, 31, 2, 3, 2, 3, 2, 37, 3, 3, 2, 41, 1, 43, 2, 3, 1, 47, 2, 8, 2, 2, 1, 53, 1, 4, 2, 3, 3, 59, 2, 61, 2, 3, 3, 3, 1, 67, 2, 2, 2, 71, 1, 73, 3, 2, 1, 3, 1, 79, 1, 3, 2, 83, 1, 4, 2, 1, 3, 89, 1, 5, 1, 3, 2, 3, 2
Offset: 1

Views

Author

Amarnath Murthy, Jun 01 2004

Keywords

Comments

a(p) = p if p is a prime. a(4) = 2 as among 8, 10,12,14, there are two multiples of 4.

Crossrefs

Programs

  • PARI
    S=Set();for(n=2,100,k=0;m=1;s=0;while(k1,S=setunion(S,[m]);k++;if(m%n==0,s++)));print1(" ",s)) (Alekseyev)

Extensions

More terms from Max Alekseyev, Jun 30 2005

A081964 In the following triangle the n-th row contains n numbers relatively prime to n and not occurring in a previous row. a(1) = 1. Sequence contains the triangle by rows.

Original entry on oeis.org

1, 3, 5, 2, 4, 7, 9, 11, 13, 15, 6, 8, 12, 14, 16, 17, 19, 23, 25, 29, 31, 10, 18, 20, 22, 24, 26, 27, 21, 33, 35, 37, 39, 41, 43, 45, 28, 32, 34, 38, 40, 44, 46, 47, 49, 51, 53, 57, 59, 61, 63, 67, 69, 71, 73, 30, 36, 42, 48, 50, 52, 54, 56, 58, 60, 62, 55, 65, 77, 79, 83, 85
Offset: 1

Views

Author

Amarnath Murthy, Apr 03 2003

Keywords

Examples

			Triangle begins:
1
3 5
2 4 7
9 11 13 15
6 8 12 14 16
...
		

Crossrefs

Cf. A095167 (noncoprime instead of coprime).

Programs

  • Perl
    See Link section.

Extensions

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 08 2003

A076034 Group the natural numbers so that the n-th group contains the smallest set of n relatively prime numbers: (1), (2, 3), (4, 5, 7), (6, 11, 13, 17), (8, 9, 19, 23, 25), (10, 21, 29, 31, 37, 41), ...

Original entry on oeis.org

1, 2, 3, 4, 5, 7, 6, 11, 13, 17, 8, 9, 19, 23, 25, 10, 21, 29, 31, 37, 41, 12, 35, 43, 47, 53, 59, 61, 14, 15, 67, 71, 73, 79, 83, 89, 16, 27, 49, 55, 97, 101, 103, 107, 109, 18, 65, 77, 113, 127, 131, 137, 139, 149, 151, 20, 33, 91, 157, 163, 167, 173, 179, 181, 191, 193
Offset: 1

Views

Author

Amarnath Murthy, Oct 01 2002

Keywords

Examples

			The triangle begins:
   1;
   2, 3;
   4,  5,  7;
   6, 11, 13, 17;
   8,  9, 19, 23, 25;
  10, 21, 29, 31, 37, 41;
  ...
		

Crossrefs

Programs

  • Maple
    S:=[$1..1000]: Res:= NULL:
    for n from 1 to 20 do
      A:= [S[1]]; R:= 1; count:= 1;
      for k from 2 while count < n do
        if andmap(t -> igcd(t,S[k])=1, A) then count:= count+1; A:= [op(A),S[k]]; R:= R,k; fi
      od;
      S:= subsop(op(map(t -> t=NULL, [R])),S);
      Res:= Res, op(A);
    od:
    Res; # Robert Israel, Dec 04 2022
  • Perl
    # See Links section.

Extensions

More terms from David Wasserman, Jan 29 2005
Crossrefs added by Paul Tek, Oct 24 2015

A095168 Leading diagonal of A095169.

Original entry on oeis.org

1, 2, 3, 8, 5, 16, 7, 32, 27, 50, 11, 69, 13, 92, 85, 122, 17, 147, 19, 145, 161, 232, 23, 273, 235, 328, 333, 287, 29, 472, 31, 520, 407, 595, 497, 639, 37, 758, 533, 755, 41, 763, 43, 649, 955, 1064, 47, 1137, 1043, 1135
Offset: 1

Views

Author

Amarnath Murthy, Jun 01 2004

Keywords

Crossrefs

Programs

  • PARI
    S=Set();for(n=2,50,k=0;m=1;while(k1,S=setunion(S,[m]);if(k==0,print1(" ",m));k++))) (Alekseyev)

Extensions

More terms from Max Alekseyev, Jun 30 2005
Showing 1-6 of 6 results.