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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.

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A106736 Primes of the form r(r(r(r(n)+1)+1)+1)+1, where A141468(n) = r(n) = n-th nonprime.

Original entry on oeis.org

2, 23, 37, 67, 71, 101, 103, 109, 127, 137, 139, 151, 157, 179, 191, 197, 199, 211, 227, 233, 239, 241, 257, 263, 271, 277, 281, 283, 311, 331, 347, 353, 359, 367, 373, 379, 389, 401, 419, 431, 443, 457, 461, 467, 499, 503, 509, 521, 523, 541, 547, 557, 563
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			n=1:
r(r(r(r(1)+1)+1)+1)+1=r(r(r(0+1)+1)+1)+1=r(r(r(1)+1)+1)+1=r(r(0+1)+1)+1=r(r(1)+1)+1=r(0+1)+1=r(1)+1=0+1=1
(nonprime).
n=2:
r(r(r(r(2)+1)+1)+1)+1=r(r(r(1+1)+1)+1)+1=r(r(r(2)+1)+1)+1=r(r(1+1)+1)+1=r(r(2)+1)+1=r(1+1)+1=r(2)+1=1+1=2=a(1).
n=3:
r(r(r(r(3)+1)+1)+1)+1=r(r(r(4+1)+1)+1)+1=r(r(r(5)+1)+1)+1=r(r(8+1)+1)+1=r(r(9)+1)+1=r(14+1)+1=r(15)+1=22+1=23=a(2).
n=4:
r(r(r(r(4)+1)+1)+1)+1=r(r(r(6+1)+1)+1)+1=r(r(r(7)+1)+1)+1=r(r(10+1)+1)+1=r(r(11)+1)+1=r(16+1)+1=r(17)+1=25+1=26
(nonprime).
n=5:
r(r(r(r(5)+1)+1)+1)+1=r(r(r(8+1)+1)+1)+1=r(r(r(9)+1)+1)+1=r(r(14+1)+1)+1=r(r(15)+1)+1=r(22+1)+1=r(23)+1=33+1=34
(nonprime).
n=6:
r(r(r(r(6)+1)+1)+1)+1=r(r(r(9+1)+1)+1)+1=r(r(r(10)+1)+1)+1=r(r(15+1)+1)+1=r(r(16)+1)+1=r(24+1)+1=r(25)+1
35+1=36 (nonprime).
n=7:
r(r(r(r(7)+1)+1)+1)+1=r(r(r(10+1)+1)+1)+1=r(r(r(11)+1)+1)+1=r(r(16+1)+1)+1=r(r(17)+1)+1=r(25+1)+1=r(26)+1
36+1=37=a(3).
n=8:
r(r(r(r(8)+1)+1)+1)+1=r(r(r(12+1)+1)+1)+1=r(r(r(13)+1)+1)+1=r(r(20+1)+1)+1=r(r(21)+1)+1=r(30+1)+1=r(31)+1=44+1=45
(nonprime).
n=9:
r(r(r(r(9)+1)+1)+1)+1=r(r(r(14+1)+1)+1)+1=r(r(r(15)+1)+1)+1=r(r(22+1)+1)+1=r(r(23)+1)+1=r(33+1)+1=r(34)+1
48+1=49 (nonprime).
n=10:
r(r(r(r(10)+1)+1)+1)+1=r(r(r(15+1)+1)+1)+1=r(r(r(16)+1)+1)+1=r(r(24+1)+1)+1=r(r(25)+1)+1=r(35+1)+1=r(36)+1
50+1=51(nonprime)
n=11:
r(r(r(r(11)+1)+1)+1)+1=r(r(r(16+1)+1)+1)+1=r(r(r(17)+1)+1)+1=r(r(25+1)+1)+1=r(r(26)+1)+1=r(36+1)+1=r(37)+1=51+1=52(nonprime),
etc.

Crossrefs

Cf. A000040, A141468.

Programs

  • Maple
    A141468 := proc(n) option remember ; if n = 1 then 0; else for a from procname(n-1)+1 do if not isprime(a) then RETURN(a); fi; od: fi; end: rep := 4: for n from 1 to 400 do arep := n ; for i from 1 to rep do arep := A141468(arep)+1 ; od: if isprime(arep) then printf("%d,",arep) ; fi; od: # R. J. Mathar, Sep 05 2008

Extensions

97 removed and extended by R. J. Mathar, Sep 05 2008

A106794 Nonprimes of the form r(r(r(r(n)+1)+1)+1)+1, where A141468(n)=r(n)=n-th nonprime.

Original entry on oeis.org

1, 26, 34, 36, 45, 49, 51, 52, 56, 63, 65, 70, 76, 77, 78, 86, 88, 91, 93, 94, 95, 105, 116, 117, 118, 121, 123, 124, 125, 133, 135, 143, 146, 153, 154, 155, 160, 161, 162, 165, 170, 172, 175, 177, 185, 187, 188, 195, 201, 203, 205, 206, 207, 208, 209, 216, 217
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n=1, then r(r(r(r(1)+1)+1)+1)+1=r(r(r(0+1)+1)+1)+1=r(r(r(1)+1)+1)+1=r(r(0+1)+1)+1=r(r(1)+1)+1=r(0+1)+1=r(1)+1=0+1=1=a(1).
If n=2, then r(r(r(r(2)+1)+1)+1)+1=r(r(r(1+1)+1)+1)+1=r(r(r(2)+1)+1)+1=r(r(1+1)+1)+1=r(r(2)+1)+1=r(1+1)+1=r(2)+1=1+1=2 (prime).
If n=3, then r(r(r(r(3)+1)+1)+1)+1=r(r(r(4+1)+1)+1)+1=r(r(r(5)+1)+1)+1=r(r(8+1)+1)+1=r(r(9)+1)+1=r(14+1)+1=r(15)+1=22+1=23 (prime).
If n=4, then r(r(r(r(4)+1)+1)+1)+1=r(r(r(6+1)+1)+1)+1=r(r(r(7)+1)+1)+1=r(r(10+1)+1)+1=r(r(11)+1)+1=r(16+1)+1=r(17)+1=25+1=26= a(2).
If n=5, then r(r(r(r(5)+1)+1)+1)+1=r(r(r(8+1)+1)+1)+1=r(r(r(9)+1)+1)+1=r(r(14+1)+1)+1=r(r(15)+1)+1=r(22+1)+1=r(23)+1=33+1=34 =a(3).
If n=6, then r(r(r(r(6)+1)+1)+1)+1=r(r(r(9+1)+1)+1)+1=r(r(r(10)+1)+1)+1=r(r(15+1)+1)+1=r(r(16)+1)+1=r(24+1)+1=r(25)+1 35+1=36=a(4).
If n=7, then r(r(r(r(7)+1)+1)+1)+1=r(r(r(10+1)+1)+1)+1=r(r(r(11)+1)+1)+1=r(r(16+1)+1)+1=r(r(17)+1)+1=r(25+1)+1=r(26)+1 36+1=37 (prime).
If n=8, then r(r(r(r(8)+1)+1)+1)+1=r(r(r(12+1)+1)+1)+1=r(r(r(13)+1)+1)+1=r(r(20+1)+1)+1=r(r(21)+1)+1=r(30+1)+1=r(31)+1=44+1=45 =a(5).
If n=9, then r(r(r(r(9)+1)+1)+1)+1=r(r(r(14+1)+1)+1)+1=r(r(r(15)+1)+1)+1=r(r(22+1)+1)+1=r(r(23)+1)+1=r(33+1)+1=r(34)+1 48+1=49=a(6).
If n=10, then r(r(r(r(10)+1)+1)+1)+1=r(r(r(15+1)+1)+1)+1=r(r(r(16)+1)+1)+1=r(r(24+1)+1)+1=r(r(25)+1)+1=r(35+1)+1=r(36)+1 50+1=51=a(7)
If n=11, then r(r(r(r(11)+1)+1)+1)+1=r(r(r(16+1)+1)+1)+1=r(r(r(17)+1)+1)+1=r(r(25+1)+1)+1=r(r(26)+1)+1=r(36+1)+1=r(37)+1=51+1=52=a(8), etc.

Crossrefs

Cf. A000040, A141468.

Extensions

91 and 123 inserted by R. J. Mathar, Sep 05 2008

A107355 Nonprimes of the form r(r(r(r(r(n)+1)+1)+1)+1)+1, where A141468(n)=r(n)=n-th nonprime.

Original entry on oeis.org

1, 34, 49, 51, 52, 63, 70, 77, 86, 88, 91, 94, 95, 105, 116, 118, 121, 123, 124, 125, 133, 135, 143, 153, 154, 160, 161, 162, 165, 172, 175, 177, 185, 188, 195, 201, 203, 206, 207, 208, 217, 219, 222, 225, 236, 238, 244, 248, 250, 253, 255, 260, 261, 262, 265
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n = 1, then
r(r(r(r(r(1)+1)+1)+1)+1)+1 = r(r(r(r(0+1)+1)+1)+1)+1 = r(r(r(r(1)+1)+1)+1)+1 = r(r(r(0+1)+1)+1)+1 = r(r(r(1)+1)+1)+1 = r(r(0+1)+1)+1 = r(r(1)+1)+1 = r(0+1)+1 = r(1)+1 = 0+1 = 1 = a(1).
If n = 2, then
r(r(r(r(r(2)+1)+1)+1)+1)+1 = r(r(r(r(1+1)+1)+1)+1)+1 = r(r(r(r(2)+1)+1)+1)+1 = r(r(r(1+1)+1)+1)+1 = r(r(r(2)+1)+1)+1 = r(r(1+1)+1)+1 = r(r(2)+1)+1 = r(1+1)+1 = r(2)+1 = 1+1 = 2
(prime).
If n = 3, then
r(r(r(r(r(3)+1)+1)+1)+1)+1 = r(r(r(r(4+1)+1)+1)+1)+1 = r(r(r(r(5)+1)+1)+1)+1 = r(r(r(8+1)+1)+1)+1 = r(r(r(9)+1)+1)+1 = r(r(14+1)+1)+1 = r(r(15)+1)+1 = r(22+1)+1 = r(23)+1 = 33+1 = 34 = a(2).
If n = 4, then
r(r(r(r(r(4)+1)+1)+1)+1)+1 = r(r(r(r(6+1)+1)+1)+1)+1 = r(r(r(r(7)+1)+1)+1)+1 = r(r(r(10+1)+1)+1)+1 = r(r(r(11)+1)+1)+1 = r(r(16+1)+1)+1 = r(r(17)+1)+1 = r(25+1)+1 = r(26)+1 = 36+1 = 37
(prime).
If n = 5, then
r(r(r(r(r(5)+1)+1)+1)+1)+1 = r(r(r(r(8+1)+1)+1)+1)+1 = r(r(r(r(9)+1)+1)+1)+1 = r(r(r(14+1)+1)+1)+1 = r(r(r(15)+1)+1)+1 = r(r(22+1)+1)+1 = r(r(23)+1)+1 = r(33+1)+1 = r(34)+1 = 48+1 = 49 = a(3).
If n = 6, then
r(r(r(r(r(6)+1)+1)+1)+1)+1 = r(r(r(r(9+1)+1)+1)+1)+1 = r(r(r(r(10)+1)+1)+1)+1 = r(r(r(15+1)+1)+1)+1 = r(r(r(16)+1)+1)+1 = r(r(24+1)+1)+1 = r(r(25)+1)+1 = r(35+1)+1 = r(36)+1 = 50+1 = 51 = a(4).
If n = 7, then
r(r(r(r(r(7)+1)+1)+1)+1)+1 = r(r(r(r(10+1)+1)+1)+1)+1 = r(r(r(r(11)+1)+1)+1)+1 = r(r(r(16+1)+1)+1)+1 = r(r(r(17)+1)+1)+1 = r(r(25+1)+1)+1 = r(r(26)+1)+1 = r(36+1)+1 = r(37)+1 = 51+1 = 52 = a(5).
If n = 8, then
r(r(r(r(r(8)+1)+1)+1)+1)+1 = r(r(r(r(12+1)+1)+1)+1)+1 = r(r(r(r(13)+1)+1)+1)+1 = r(r(r(20+1)+1)+1)+1 = r(r(r(21)+1)+1)+1 = r(r(30+1)+1)+1 = r(r(31)+1)+1 = r(44+1)+1 = r(45)+1 = 62+1 = 63 = a(6).
If n = 9, then
r(r(r(r(r(9)+1)+1)+1)+1)+1 = r(r(r(r(14+1)+1)+1)+1)+1 = r(r(r(r(15)+1)+1)+1)+1 = r(r(r(22+1)+1)+1)+1 = r(r(r(23)+1)+1)+1 = r(r(33+1)+1)+1 = r(r(34)+1)+1 = r(48+1)+1 = r(49)+1 = 66+1 = 67
(prime).
If n = 10, then
r(r(r(r(r(10)+1)+1)+1)+1)+1 = r(r(r(r(15+1)+1)+1)+1)+1 = r(r(r(r(16)+1)+1)+1)+1 = r(r(r(24+1)+1)+1)+1 = r(r(r(25)+1)+1)+1 = r(r(35+1)+1)+1 = r(r(36)+1)+1 = r(50+1)+1 = r(51)+1 = 69+1 = 70 = a(7)
If n = 11, then
r(r(r(r(r(11)+1)+1)+1)+1)+1 = r(r(r(r(16+1)+1)+1)+1)+1 = r(r(r(r(17)+1)+1)+1)+1 = r(r(r(25+1)+1)+1)+1 = r(r(r(26)+1)+1)+1 = r(r(36+1)+1)+1 = r(r(37)+1)+1 = r(51+1)+1 = r(52)+1 = 70+1 = 71(prime),
etc.

Crossrefs

Cf. A000040, A141468.

Extensions

Removed 36, inserted 121 and 160 by R. J. Mathar, Sep 05 2008

A107752 Primes of the form r(r(r(r(r(n)+1)+1)+1)+1)+1, where A141468(n)=r(n)=n-th nonprime.

Original entry on oeis.org

2, 37, 67, 71, 101, 103, 137, 151, 157, 179, 197, 199, 211, 227, 239, 257, 263, 277, 281, 311, 331, 347, 353, 359, 367, 373, 379, 401, 419, 443, 457, 461, 467, 499, 503, 509, 521, 523, 541, 563, 571, 577, 587, 613, 641, 647, 659, 661, 673, 677, 709, 719, 733
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n = 1, then
r(r(r(r(r(1)+1)+1)+1)+1)+1 = r(r(r(r(0+1)+1)+1)+1)+1 = r(r(r(r(1)+1)+1)+1)+1 = r(r(r(0+1)+1)+1)+1 = r(r(r(1)+1)+1)+1 = r(r(0+1)+1)+1 = r(r(1)+1)+1 = r(0+1)+1 = r(1)+1 = 0+1 = 1
(nonprime).
If n = 2, then
r(r(r(r(r(2)+1)+1)+1)+1)+1 = r(r(r(r(1+1)+1)+1)+1)+1 = r(r(r(r(2)+1)+1)+1)+1 = r(r(r(1+1)+1)+1)+1 = r(r(r(2)+1)+1)+1 = r(r(1+1)+1)+1 = r(r(2)+1)+1 = r(1+1)+1 = r(2)+1 = 1+1 = 2 = a(1).
If n = 3, then
r(r(r(r(r(3)+1)+1)+1)+1)+1 = r(r(r(r(4+1)+1)+1)+1)+1 = r(r(r(r(5)+1)+1)+1)+1 = r(r(r(8+1)+1)+1)+1 = r(r(r(9)+1)+1)+1 = r(r(14+1)+1)+1 = r(r(15)+1)+1 = r(22+1)+1 = r(23)+1 = 33+1 = 34
(nonprime).
If n = 4, then
r(r(r(r(r(4)+1)+1)+1)+1)+1 = r(r(r(r(6+1)+1)+1)+1)+1 = r(r(r(r(7)+1)+1)+1)+1 = r(r(r(10+1)+1)+1)+1 = r(r(r(11)+1)+1)+1 = r(r(16+1)+1)+1 = r(r(17)+1)+1 = r(25+1)+1 = r(26)+1 = 36+1 = 37 = a(2).
If n = 5, then
r(r(r(r(r(5)+1)+1)+1)+1)+1 = r(r(r(r(8+1)+1)+1)+1)+1 = r(r(r(r(9)+1)+1)+1)+1 = r(r(r(14+1)+1)+1)+1 = r(r(r(15)+1)+1)+1 = r(r(22+1)+1)+1 = r(r(23)+1)+1 = r(33+1)+1 = r(34)+1 = 48+1 = 49
(nonprime).
If n = 6, then
r(r(r(r(r(6)+1)+1)+1)+1)+1 = r(r(r(r(9+1)+1)+1)+1)+1 = r(r(r(r(10)+1)+1)+1)+1 = r(r(r(15+1)+1)+1)+1 = r(r(r(16)+1)+1)+1 = r(r(24+1)+1)+1 = r(r(25)+1)+1 = r(35+1)+1 = r(36)+1 = 50+1 = 51
(nonprime).
If n = 7, then
r(r(r(r(r(7)+1)+1)+1)+1)+1 = r(r(r(r(10+1)+1)+1)+1)+1 = r(r(r(r(11)+1)+1)+1)+1 = r(r(r(16+1)+1)+1)+1 = r(r(r(17)+1)+1)+1 = r(r(25+1)+1)+1 = r(r(26)+1)+1 = r(36+1)+1 = r(37)+1 = 51+1 = 52
(nonprime).
If n = 8, then
r(r(r(r(r(8)+1)+1)+1)+1)+1 = r(r(r(r(12+1)+1)+1)+1)+1 = r(r(r(r(13)+1)+1)+1)+1 = r(r(r(20+1)+1)+1)+1 = r(r(r(21)+1)+1)+1 = r(r(30+1)+1)+1 = r(r(31)+1)+1 = r(44+1)+1 = r(45)+1 = 62+1 = 63
(nonprime).
If n = 9, then
r(r(r(r(r(9)+1)+1)+1)+1)+1 = r(r(r(r(14+1)+1)+1)+1)+1 = r(r(r(r(15)+1)+1)+1)+1 = r(r(r(22+1)+1)+1)+1 = r(r(r(23)+1)+1)+1 = r(r(33+1)+1)+1 = r(r(34)+1)+1 = r(48+1)+1 = r(49)+1 = 66+1 = 67 = a
(3).
If n = 10, then
r(r(r(r(r(10)+1)+1)+1)+1)+1 = r(r(r(r(15+1)+1)+1)+1)+1 = r(r(r(r(16)+1)+1)+1)+1 = r(r(r(24+1)+1)+1)+1 = r(r(r(25)+1)+1)+1 = r(r(35+1)+1)+1 = r(r(36)+1)+1 = r(50+1)+1 = r(51)+1 = 69+1 = 70
(nonprime)
If n = 11, then
r(r(r(r(r(11)+1)+1)+1)+1)+1 = r(r(r(r(16+1)+1)+1)+1)+1 = r(r(r(r(17)+1)+1)+1)+1 = r(r(r(25+1)+1)+1)+1 = r(r(r(26)+1)+1)+1 = r(r(36+1)+1)+1 = r(r(37)+1)+1 = r(51+1)+1 = r(52)+1 = 70+1 = 71 = a(4),
etc.

Crossrefs

Cf. A000040, A141468.

Extensions

127 removed, 151 added, 407 removed and extended by R. J. Mathar, Sep 05 2008

A107993 Primes of the form r(r(r(r(r(r(n)+1)+1)+1)+1)+1)+1, where A141468(n) = r(n) = n-th nonprime.

Original entry on oeis.org

2, 67, 71, 103, 137, 151, 157, 197, 199, 211, 227, 239, 257, 263, 277, 281, 311, 331, 359, 367, 373, 401, 419, 457, 461, 467, 499, 503, 521, 523, 541, 563, 571, 577, 587, 613, 641, 647, 661, 673, 677, 709, 719, 733, 739, 743, 761, 797, 809, 811, 821, 829
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n = 1, then
r(r(r(r(r(r(1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(0+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1)+1)+1)+1)+1)+1 = r(r(r(r(0+1)+1)+1)+1)+1 = r(r(r(r(1)+1)+1)+1)+1 = r(r(r(0+1)+1)+1)+1 = r(r(r(1)+1)+1)+1 = r(r(0+1)+1)+1 = r(r(1)+1)+1 = r(0+1)+1 = r(1)+1 = 0+1 = 1
(nonprime).
If n = 2, then
r(r(r(r(r(r(2)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1+1)+1)+1)+1)+1)+1 = r(r(r(r(r(2)+1)+1)+1)+1)+1 = r(r(r(r(1+1)+1)+1)+1)+1 = r(r(r(r(2)+1)+1)+1)+1 = r(r(r(1+1)+1)+1)+1 = r(r(r(2)+1)+1)+1 = r(r(1+1)+1)+1 = r(r(2)+1)+1 = r(1+1)+1 = r(2)+1 = 1+1 = 2 = a(1).
If n = 3, then
r(r(r(r(r(r(3)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(4+1)+1)+1)+1)+1)+1 = r(r(r(r(r(5)+1)+1)+1)+1)+1 = r(r(r(r(8+1)+1)+1)+1)+1 = r(r(r(r(9)+1)+1)+1)+1 = r(r(r(14+1)+1)+1)+1 = r(r(r(15)+1)+1)+1 = r(r(22+1)+1)+1 = r(r(23)+1)+1 = r(33+1)+1 = r(34)+1 = 48+1 = 49
(nonprime).
If n = 4, then
r(r(r(r(r(r(4)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(6+1)+1)+1)+1)+1)+1 = r(r(r(r(r(7)+1)+1)+1)+1)+1 = r(r(r(r(10+1)+1)+1)+1)+1 = r(r(r(r(11)+1)+1)+1)+1 = r(r(r(16+1)+1)+1)+1 = r(r(r(17)+1)+1)+1 = r(r(25+1)+1)+1 = r(r(26)+1)+1 = r(36+1)+1 = r(37)+1 = 51+1 = 52
(nonprime).
If n = 5, then
r(r(r(r(r(r(5)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(8+1)+1)+1)+1)+1)+1 = r(r(r(r(r(9)+1)+1)+1)+1)+1 = r(r(r(r(14+1)+1)+1)+1)+1 = r(r(r(r(15)+1)+1)+1)+1 = r(r(r(22+1)+1)+1)+1 = r(r(r(23)+1)+1)+1 = r(r(33+1)+1)+1 = r(r(34)+1)+1 = r(48+1)+1 = r(49)+1 = 66+1 = 67 = a(2).
If n = 6, then
r(r(r(r(r(r(6)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(9+1)+1)+1)+1)+1)+1 = r(r(r(r(r(10)+1)+1)+1)+1)+1 = r(r(r(r(15+1)+1)+1)+1)+1 = r(r(r(r(16)+1)+1)+1)+1 = r(r(r(24+1)+1)+1)+1 = r(r(r(25)+1)+1)+1 = r(r(35+1)+1)+1 = r(r(36)+1)+1 = r(50+1)+1 = r(51)+169+1 = 70
(nonprime).
If n = 7, then
r(r(r(r(r(r(7)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(10+1)+1)+1)+1)+1)+1 = r(r(r(r(r(11)+1)+1)+1)+1)+1 = r(r(r(r(16+1)+1)+1)+1)+1 = r(r(r(r(17)+1)+1)+1)+1 = r(r(r(25+1)+1)+1)+1 = r(r(r(26)+1)+1)+1 = r(r(36+1)+1)+1 = r(r(37)+1)+1 = r(51+1)+1 = r(52)+1 = 70+1 = 71 = a
(4).
If n = 8, then
r(r(r(r(r(r(8)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(12+1)+1)+1)+1)+1)+1 = r(r(r(r(r(13)+1)+1)+1)+1)+1 = r(r(r(r(20+1)+1)+1)+1)+1 = r(r(r(r(21)+1)+1)+1)+1 = r(r(r(30+1)+1)+1)+1 = r(r(r(31)+1)+1)+1 = r(r(44+1)+1)+1 = r(r(45)+1)+1 = r(62+1)+1 = r(63)+1 = 85+1 = 86
(nonprime).
If n = 9, then
r(r(r(r(r(r(9)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(14+1)+1)+1)+1)+1)+1 = r(r(r(r(r(15)+1)+1)+1)+1)+1 = r(r(r(r(22+1)+1)+1)+1)+1 = r(r(r(r(23)+1)+1)+1)+1 = r(r(r(33+1)+1)+1)+1 = r(r(r(34)+1)+1)+1 = r(r(48+1)+1)+1 = r(r(49)+1)+1 = r(66+1)+1 = r(67)+1 = 90+1 = 91
(nonprime), etc.

Crossrefs

Cf. A000040, A141468.

Extensions

179 replaced by 157, 257 inserted and extended by R. J. Mathar, Sep 05 2008

A118073 Nonprimes of the form r(r(r(r(r(r(n)+1)+1)+1)+1)+1)+1, where A141468(n)=r(n)=n-th nonprime.

Original entry on oeis.org

1, 49, 52, 70, 86, 91, 94, 95, 116, 118, 121, 124, 125, 133, 135, 154, 160, 161, 162, 172, 175, 177, 185, 195, 203, 206, 207, 208, 219, 222, 225, 236, 248, 250, 253, 255, 261, 262, 267, 275, 286, 288, 298, 300, 301, 306, 315, 319, 321, 323, 326, 327, 328, 329
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n = 1, then
r(r(r(r(r(r(1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(0+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1)+1)+1)+1)+1)+1 = r(r(r(r(0+1)+1)+1)+1)+1 = r(r(r(r(1)+1)+1)+1)+1 = r(r(r(0+1)+1)+1)+1 = r(r(r(1)+1)+1)+1 = r(r(0+1)+1)+1 = r(r(1)+1)+1 = r(0+1)+1 = r(1)+1 = 0+1 = 1 = a(1).
If n = 2, then
r(r(r(r(r(r(2)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1+1)+1)+1)+1)+1)+1 = r(r(r(r(r(2)+1)+1)+1)+1)+1 = r(r(r(r(1+1)+1)+1)+1)+1 = r(r(r(r(2)+1)+1)+1)+1 = r(r(r(1+1)+1)+1)+1 = r(r(r(2)+1)+1)+1 = r(r(1+1)+1)+1 = r(r(2)+1)+1 = r(1+1)+1 = r(2)+1 = 1+1 = 2
(prime).
If n = 3, then
r(r(r(r(r(r(3)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(4+1)+1)+1)+1)+1)+1 = r(r(r(r(r(5)+1)+1)+1)+1)+1 = r(r(r(r(8+1)+1)+1)+1)+1 = r(r(r(r(9)+1)+1)+1)+1 = r(r(r(14+1)+1)+1)+1 = r(r(r(15)+1)+1)+1 = r(r(22+1)+1)+1 = r(r(23)+1)+1 = r(33+1)+1 = r(34)+1 = 48+1 = 49 = a(2).
If n = 4, then
r(r(r(r(r(r(4)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(6+1)+1)+1)+1)+1)+1 = r(r(r(r(r(7)+1)+1)+1)+1)+1 = r(r(r(r(10+1)+1)+1)+1)+1 = r(r(r(r(11)+1)+1)+1)+1 = r(r(r(16+1)+1)+1)+1 = r(r(r(17)+1)+1)+1 = r(r(25+1)+1)+1 = r(r(26)+1)+1 = r(36+1)+1 = r(37)+1 = 51+1 = 52 = a(3).
If n = 5, then
r(r(r(r(r(r(5)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(8+1)+1)+1)+1)+1)+1 = r(r(r(r(r(9)+1)+1)+1)+1)+1 = r(r(r(r(14+1)+1)+1)+1)+1 = r(r(r(r(15)+1)+1)+1)+1 = r(r(r(22+1)+1)+1)+1 = r(r(r(23)+1)+1)+1 = r(r(33+1)+1)+1 = r(r(34)+1)+1 = r(48+1)+1 = r(49)+1 = 66+1 = 67
(prime).
If n = 6, then
r(r(r(r(r(r(6)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(9+1)+1)+1)+1)+1)+1 = r(r(r(r(r(10)+1)+1)+1)+1)+1 = r(r(r(r(15+1)+1)+1)+1)+1 = r(r(r(r(16)+1)+1)+1)+1 = r(r(r(24+1)+1)+1)+1 = r(r(r(25)+1)+1)+1 = r(r(35+1)+1)+1 = r(r(36)+1)+1 = r(50+1)+1 = r(51)+169+1 = 70 = a
(4).
If n = 7, then
r(r(r(r(r(r(7)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(10+1)+1)+1)+1)+1)+1 = r(r(r(r(r(11)+1)+1)+1)+1)+1 = r(r(r(r(16+1)+1)+1)+1)+1 = r(r(r(r(17)+1)+1)+1)+1 = r(r(r(25+1)+1)+1)+1 = r(r(r(26)+1)+1)+1 = r(r(36+1)+1)+1 = r(r(37)+1)+1 = r(51+1)+1 = r(52)+1 = 70+1 = 71
(prime).
If n = 8, then
r(r(r(r(r(r(8)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(12+1)+1)+1)+1)+1)+1 = r(r(r(r(r(13)+1)+1)+1)+1)+1 = r(r(r(r(20+1)+1)+1)+1)+1 = r(r(r(r(21)+1)+1)+1)+1 = r(r(r(30+1)+1)+1)+1 = r(r(r(31)+1)+1)+1 = r(r(44+1)+1)+1 = r(r(45)+1)+1 = r(62+1)+1 = r(63)+1 = 85+1 = 86 = a
(5).
If n = 9, then
r(r(r(r(r(r(9)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(14+1)+1)+1)+1)+1)+1 = r(r(r(r(r(15)+1)+1)+1)+1)+1 = r(r(r(r(22+1)+1)+1)+1)+1 = r(r(r(r(23)+1)+1)+1)+1 = r(r(r(33+1)+1)+1)+1 = r(r(r(34)+1)+1)+1 = r(r(48+1)+1)+1 = r(r(49)+1)+1 = r(66+1)+1 = r(67)+1 = 90+1 = 91 = a(6),
etc.

Crossrefs

Cf. A000040, A141468.

Extensions

165 removed, 206 added, 257 removed by R. J. Mathar, Sep 05 2008

A126134 Nonprimes of the form r(r(r(r(r(r(r(n)+1)+1)+1)+1)+1)+1)+1, where A141468(n) = r(n) = n-th nonprime.

Original entry on oeis.org

1, 91, 94, 95, 116, 121, 124, 125, 135, 154, 161, 162, 172, 175, 177, 195, 203, 206, 207, 208, 219, 222, 225, 236, 248, 250, 253, 261, 262, 267, 286, 288, 298, 301, 315, 319, 321, 323, 327, 328, 329, 334, 343, 345, 351, 357, 371, 375, 381, 387, 392, 396, 399
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			If n = 1, then
r(r(r(r(r(r(r(1)+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(0+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(0+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1)+1)+1)+1)+1)+1 = r(r(r(r(0+1)+1)+1)+1)+1 = r(r(r(r(1)+1)+1)+1)+1 = r(r(r(0+1)+1)+1)+1 = r(r(r(1)+1)+1)+1 = r(r(0+1)+1)+1 = r(r(1)+1)+1 = r(0+1)+1 = r(1)+1 = 0+1 = 1 = a(1).
If n = 2, then
r(r(r(r(r(r(r(2)+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(1+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(2)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(1+1)+1)+1)+1)+1)+1 = r(r(r(r(r(2)+1)+1)+1)+1)+1 = r(r(r(r(1+1)+1)+1)+1)+1 = r(r(r(r(2)+1)+1)+1)+1 = r(r(r(1+1)+1)+1)+1 = r(r(r(2)+1)+1)+1 = r(r(1+1)+1)+1 = r(r(2)+1)+1 = r(1+1)+1 = r(2)+1 = 1+1 = 2
(prime).
If n = 3, then
r(r(r(r(r(r(r(3)+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(4+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(5)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(8+1)+1)+1)+1)+1)+1 = r(r(r(r(r(9)+1)+1)+1)+1)+1 = r(r(r(r(14+1)+1)+1)+1)+1 = r(r(r(r(15)+1)+1)+1)+1 = r(r(r(22+1)+1)+1)+1 = r(r(r(23)+1)+1)+1 = r(r(33+1)+1)+1 = r(r(34)+1)+1 = r(48+1)+1 = r(49)+1 = 66+1 = 67(prime).
If n = 4, then
r(r(r(r(r(r(r(4)+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(6+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(7)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(10+1)+1)+1)+1)+1)+1 = r(r(r(r(r(11)+1)+1)+1)+1)+1 = r(r(r(r(16+1)+1)+1)+1)+1 = r(r(r(r(17)+1)+1)+1)+1 = r(r(r(25+1)+1)+1)+1 = r(r(r(26)+1)+1)+1 = r(r(36+1)+1)+1 = r(r(37)+1)+1 = r(51+1)+1 = r(52)+1 = 70+1 = 71(prime).
If n = 5, then
r(r(r(r(r(r(r(5)+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(8+1)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(r(9)+1)+1)+1)+1)+1)+1 = r(r(r(r(r(14+1)+1)+1)+1)+1)+1 = r(r(r(r(r(15)+1)+1)+1)+1)+1 = r(r(r(r(22+1)+1)+1)+1)+1 = r(r(r(r(23)+1)+1)+1)+1 = r(r(r(33+1)+1)+1)+1 = r(r(r(34)+1)+1)+1 = r(r(48+1)+1)+1 = r(r(49)+1)+1 = r(66+1)+1 = r(67)+1 = 90+1 = 91 = a(2),
etc.

Crossrefs

Cf. A000040, A141468.

Extensions

160 removed, 165 removed, 203 added, 261 added, etc. by R. J. Mathar, Sep 05 2008

A131604 Primes of the form r(r(r(r(r(r(r(k)+1)+1)+1)+1)+1)+1)+1, where r(k) = A141468(k) = k-th nonprime.

Original entry on oeis.org

2, 67, 71, 151, 157, 199, 257, 263, 277, 281, 311, 359, 373, 401, 461, 467, 499, 503, 521, 523, 541, 563, 571, 577, 613, 641, 661, 673, 677, 733, 739, 743, 761, 809, 829, 859, 863, 911, 929, 941, 967, 983, 991, 1019, 1031, 1051, 1063, 1093, 1103, 1123
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 25 2008

Keywords

Examples

			At k=3, we have
    r(r(r(r(r(r(r(3)+1)+1)+1)+1)+1)+1)+1
  = r(r(r(r(r(r(4+1)+1)+1)+1)+1)+1)+1
  = r(r(r(r(r(r(5)+1)+1)+1)+1)+1)+1
  = r(r(r(r(r(8+1)+1)+1)+1)+1)+1
  = r(r(r(r(r(9)+1)+1)+1)+1)+1
  = r(r(r(r(14+1)+1)+1)+1)+1
  = r(r(r(r(15)+1)+1)+1)+1
  = r(r(r(22+1)+1)+1)+1
  = r(r(r(23)+1)+1)+1
  = r(r(33+1)+1)+1
  = r(r(34)+1)+1
  = r(48+1)+1
  = r(49)+1
  = 66+1
  = 67.

Crossrefs

Cf. A000040, A141468.

Extensions

211 removed, 355 replaced by 359 and extended by R. J. Mathar, Sep 05 2008

A141560 Nonprimes of form (prime(n)-r(n)), where A141468(n)=r(n)=n-th nonprime and prime(n)=n-th prime.

Original entry on oeis.org

1, 1, 4, 9, 14, 15, 21, 22, 25, 34, 35, 40, 50, 55, 62, 65, 65, 68, 69, 86, 91, 91, 100, 106, 111, 118, 123, 124, 133, 133, 135, 136, 147, 158, 161, 161, 164, 169, 169, 177, 182, 187, 192, 200, 201, 209, 222, 225, 226, 246, 255, 256, 259, 264, 275, 280, 287, 296
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Aug 14 2008

Keywords

Crossrefs

Cf. A000040, A141468.

Programs

  • Mathematica
    Module[{nn=200,np,len},np=Select[Range[0,nn],!PrimeQ[#]&];len= Length[ np];Select[ #[[1]]-#[[2]]&/@Thread[{Prime[Range[len]],np}],!PrimeQ[ #]&]] (* Harvey P. Dale, Oct 15 2020 *)

Extensions

Edited, corrected and extended by Ray Chandler, Aug 19 2008

A141784 Primes of the form A141468(n)-n, where A141468(n)=n-th nonprime.

Original entry on oeis.org

2, 3, 3, 3, 5, 5, 5, 7, 7, 7, 11, 11, 11, 13, 13, 13, 17, 17, 17, 17, 17, 19, 23, 23, 23, 23, 23, 23, 23, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 31, 37, 37, 37, 41, 41, 41, 41, 41, 41, 41, 41, 41, 43, 43, 43, 47, 47, 47, 53, 53, 53, 53, 53, 59, 61, 61, 61, 61
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Sep 13 2008

Keywords

Examples

			n=4: k(4)-4=6-4=2=a(1).
n=5: k(5)-5=8-5=3=a(2).
n=6: k(6)-6=9-6=3=a(3).
n=7: k(7)-7=10-7=3=a(4).
n=9: k(9)-9=14-9=5=a(5).

Crossrefs

Cf. A000040, A051697, A141468.

Extensions

Extended by R. J. Mathar, Sep 26 2008
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