A250046 -id:A250046 - cp's OEIS frontend

A250047 Numbers n such that m = floor(n/7) is not coprime to n and, if nonzero, m is also a term of the sequence.

2, 3, 4, 5, 6, 14, 16, 18, 20, 21, 24, 27, 28, 30, 32, 34, 35, 40, 42, 44, 45, 46, 48, 98, 100, 102, 104, 112, 114, 116, 118, 126, 128, 129, 130, 132, 140, 142, 144, 145, 146, 147, 150, 153, 168, 170, 171, 172, 174, 189, 192, 195, 196, 198, 200, 202, 210

Offset: 1

Stanislav Sykora, Jan 15 2015

See the comments in A250041 which all apply, except for the setting of the base, b=7. In particular, they define the property RTNC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments
Wikipedia, Coprime integers

Cf. A250041 (b=10), A250046.
Other lists of right-truncatable numbers with the property RTNC(b):
A005823 (b=3), A250037 (b=4), A250039 (b=16), A250043 (b=9), A250045 (b=8), A250049 (b=6), A250051 (b=5).

PARI
```
See the link
```

is_rtnc(n, b=7) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b; ); return (0); } \\ Michel Marcus, Jan 22 2015

A250036 Numbers n such that m = floor(n/4) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 4, 5, 6, 7, 17, 19, 21, 22, 23, 25, 29, 30, 31, 69, 70, 71, 77, 78, 79, 85, 86, 89, 91, 93, 94, 95, 101, 102, 103, 117, 118, 119, 121, 125, 126, 127, 277, 278, 281, 283, 285, 286, 287, 309, 310, 311, 313, 317, 318, 319, 341, 342, 343, 345, 347, 357, 358

Offset: 1

Stanislav Sykora, Dec 07 2014

See the comments in A250040 which all apply, except for the setting of the base, b=4. In particular, they define the property RTC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250037, A250040.

Other lists of right-truncatable numbers with the property RTC(b): A250038 (b=16), A250040 (b=10), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).

PARI
```
See the link.
```

is_rtc(n, b=4) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 18 2015

A250038 Numbers n such that m = floor(n/16) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 257, 259, 261, 263, 265, 267, 269, 271, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 289, 293, 295, 299, 301, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314

Offset: 1

Stanislav Sykora, Dec 07 2014

See the comments in A250040 which all apply, except for the setting of the base, b=16. In particular, they define the property RTC(b).

This particular list is an infinite subset of A248501.

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A248501, A250039, A250040.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250040 (b=10), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).

PARI
```
See the link.
```

is_rtc(n, b=16) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 18 2015

A250040 Numbers n such that m = floor(n/10) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 101, 103, 107, 109, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 125, 127, 131, 132, 133, 134, 135, 136, 137, 138, 139, 141, 143, 145, 149, 151, 152, 154, 157, 158, 161, 163, 165, 167, 169, 171, 172, 173, 174, 175

Offset: 1

Stanislav Sykora, Dec 07 2014

Equivalent definition 1: Assuming a base b (in this case b=10), let us say that a positive integer k has the property RTC(b) when m=floor(k/b) is coprime to k, i.e., gcd(k,m)=1. Then k belongs to this sorted list if (i) it has the property RTC(b) and (ii) m is either 0 or belongs also to the list.
Equivalent definition 2: Every nonempty prefix of a(n) in base b has the property RTC(b).
Notes: The acronym RTC stands for 'Right-Truncated is Coprime'. We could also say that a(n) are right-truncatable numbers with property RTC(b).
This particular list is an infinite subset of A248499.

			149, 14, and 1 are members because (149,14), (14,1) and (1,0) are all coprime pairs.
67 is not a member because gcd(67,7)=1, but gcd(6,0)=6.

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A248499, A250041.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250038 (b=16), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).

F:= proc(a) seq(10*a+d, d = select(t -> igcd(a,t)=1, [$0..9])) end proc:
B[1]:= [1]:
for i from 2 to 4 do
  B[i]:= map(F,B[i-1]);
od:
ListTools:-Flatten([seq(B[i],i=1..4)]); # Robert Israel, Jan 04 2015

PARI
```
See the link.
```

is_rtc(n, b=10) = {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 17 2015

A250042 Numbers n such that m = floor(n/9) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 9, 10, 11, 12, 13, 14, 15, 16, 17, 82, 83, 85, 86, 88, 89, 91, 93, 97, 100, 101, 102, 103, 104, 105, 106, 107, 109, 113, 115, 118, 119, 120, 121, 122, 123, 124, 125, 127, 129, 131, 136, 137, 139, 142, 143, 145, 147, 149, 151, 154, 155, 156, 157, 158

Offset: 1

Stanislav Sykora, Jan 15 2015

See the comments in A250040 which all apply, except for the setting of the base, b=9. In particular, they define the property RTC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250040 (b=10), A250043.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250038 (b=16), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).

PARI
```
See the link
```

is_rtc(n, b=9) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 18 2015

A250044 Numbers n such that m = floor(n/8) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 8, 9, 10, 11, 12, 13, 14, 15, 65, 67, 69, 71, 73, 74, 76, 77, 79, 81, 83, 87, 89, 90, 91, 92, 93, 94, 95, 97, 101, 103, 105, 106, 107, 108, 109, 110, 111, 113, 115, 117, 121, 122, 124, 127, 521, 522, 523, 524, 526, 527, 537

Offset: 1

Stanislav Sykora, Jan 15 2015

See the comments in A250040 which all apply, except for the setting of the base, b=8. In particular, they define the property RTC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250040 (b=10), A250045.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250038 (b=16), A250042 (b=9), A250046 (b=7), A250048 (b=6), A250050 (b=5).

PARI
```
See the link
```

is_rtc(n, b=8) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 18 2015

A250048 Numbers n such that m = floor(n/6) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 6, 7, 8, 9, 10, 11, 37, 41, 43, 44, 45, 46, 47, 49, 51, 53, 55, 56, 58, 59, 61, 63, 67, 68, 69, 70, 71, 223, 224, 225, 226, 227, 247, 248, 249, 250, 251, 259, 260, 261, 262, 263, 265, 267, 269, 271, 272, 274, 277, 279, 281, 283, 284, 285, 286, 287, 295

Offset: 1

Stanislav Sykora, Jan 31 2015

See the comments in A250040 which all apply, except for the setting of the base, b=6. In particular, they define the property RTC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250040 (b=10), A250047.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250038 (b=16), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250050 (b=5).

PARI
```
\\ See A250040 for b=6
```

is_rtc(n, b=6) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 31 2015

A250049 Numbers n such that m = floor(n/6) is not coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

2, 3, 4, 5, 12, 14, 16, 18, 21, 24, 26, 28, 30, 35, 72, 74, 75, 76, 84, 86, 88, 96, 98, 100, 108, 110, 111, 112, 126, 129, 144, 146, 147, 148, 156, 158, 160, 168, 170, 172, 180, 182, 183, 184, 185, 210, 215, 432, 434, 435, 436, 444, 446, 448, 450, 453, 455

Offset: 1

Stanislav Sykora, Jan 31 2015

See the comments in A250041 which all apply, except for the setting of the base, b=6. In particular, they define the property RTNC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250041 (b=10), A250046.
Other lists of right-truncatable numbers with the property RTNC(b):
A005823 (b=3), A250037 (b=4), A250039 (b=16), A250043 (b=9), A250045 (b=8), A250047 (b=7), A250051 (b=5).

PARI
```
\\ See A250041 for b=6
```

is_rtnc(n, b=6) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b;); return (0); } \\ Michel Marcus, Jan 31 2015

A250050 Numbers n such that m = floor(n/5) is coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

1, 5, 6, 7, 8, 9, 26, 27, 28, 29, 31, 36, 37, 38, 39, 41, 43, 46, 47, 49, 131, 133, 136, 137, 139, 141, 143, 146, 147, 148, 149, 156, 157, 158, 159, 181, 186, 187, 188, 189, 191, 193, 196, 197, 199, 206, 207, 208, 209, 216, 217, 218, 219, 231, 233, 236, 237

Offset: 1

Stanislav Sykora, Jan 31 2015

See the comments in A250040 which all apply, except for the setting of the base, b=5. In particular, they define the property RTC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250040 (b=10), A250047.

Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250038 (b=16), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6).

PARI
```
\\ See A250040 for b=5
```

is_rtc(n, b=5) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ Michel Marcus, Jan 31 2015

A250051 Numbers n such that m = floor(n/5) is not coprime to n and, if nonzero, m is also a term of the sequence.

Original entry on oeis.org

2, 3, 4, 10, 12, 14, 15, 18, 20, 22, 24, 50, 52, 54, 60, 62, 63, 64, 70, 72, 74, 75, 78, 90, 92, 93, 94, 100, 102, 104, 110, 112, 114, 120, 122, 123, 124, 250, 252, 254, 260, 262, 264, 270, 272, 273, 274, 300, 302, 303, 304, 310, 312, 314, 315, 318

Offset: 1

Stanislav Sykora, Jan 31 2015

See the comments in A250041 which all apply, except for the setting of the base, b=5. In particular, they define the property RTNC(b).

Stanislav Sykora, Table of n, a(n) for n = 1..10000
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers

Cf. A250041 (b=10), A250046.
Other lists of right-truncatable numbers with the property RTNC(b):
A005823 (b=3), A250037 (b=4), A250039 (b=16), A250043 (b=9), A250045 (b=8), A250047 (b=7), A250049 (b=6).

PARI
```
\\ See A250041 for b=5
```

is_rtnc(n, b=5) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b;); return (0);} \\ Michel Marcus, Jan 31 2015

cp's OEIS Frontend

A250047 Numbers n such that m = floor(n/7) is not coprime to n and, if nonzero, m is also a term of the sequence.

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A250036 Numbers n such that m = floor(n/4) is coprime to n and, if nonzero, m is also a term of the sequence.

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A250038 Numbers n such that m = floor(n/16) is coprime to n and, if nonzero, m is also a term of the sequence.

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A250040 Numbers n such that m = floor(n/10) is coprime to n and, if nonzero, m is also a term of the sequence.

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Maple

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PARI

A250042 Numbers n such that m = floor(n/9) is coprime to n and, if nonzero, m is also a term of the sequence.

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PARI

PARI

A250044 Numbers n such that m = floor(n/8) is coprime to n and, if nonzero, m is also a term of the sequence.

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PARI

PARI

A250048 Numbers n such that m = floor(n/6) is coprime to n and, if nonzero, m is also a term of the sequence.

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PARI

PARI

A250049 Numbers n such that m = floor(n/6) is not coprime to n and, if nonzero, m is also a term of the sequence.

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