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 1-7 of 7 results.

A199124 Least prime having 1 more digit and higher sum of digits than the preceding term.

Original entry on oeis.org

2, 13, 107, 1009, 10037, 100049, 1000099, 10000379, 100000399, 1000000787, 10000000799, 100000001989, 1000000001999, 10000000003999, 100000000006997, 1000000000017899, 10000000000018999, 100000000000038989, 1000000000000067999, 10000000000000079899, 100000000000000079999
Offset: 1

Views

Author

M. F. Hasler, Nov 03 2011

Keywords

Comments

For more terms use the formula a(n)=10^(n-1)+A199190(n) and the values listed in A199190.

Crossrefs

Cf. A065122.

Programs

  • PARI
    {print1(p=2);for(d=1,20,o=A007953(p);p=10^d; until(A007953(p=nextprime(p+1))>o,);print1(","p))}

Formula

A199124(n) = 10^(n-1)+A199190(n); see there for an estimate of growth.

A065533 a(n) is smallest prime > 10*a(n-1), a(1) = 3.

Original entry on oeis.org

3, 31, 311, 3119, 31193, 311951, 3119533, 31195343, 311953441, 3119534441, 31195344413, 311953444133, 3119534441393, 31195344413953, 311953444139539, 3119534441395579, 31195344413955853, 311953444139558593
Offset: 1

Views

Author

Robert G. Wilson v, Nov 28 2001

Keywords

Crossrefs

Cf. A065122.

Programs

  • Mathematica
    NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 3; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
    NestList[NextPrime[10#]&,3,20] (* Harvey P. Dale, Jul 04 2012 *)
  • PARI
    { for (n=1, 100, if (n>1, a=nextprime(10*a), a=3); write("b065533.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 21 2009

A065534 a(n) is smallest prime > 10*a(n-1), a(1) = 5.

Original entry on oeis.org

5, 53, 541, 5413, 54133, 541339, 5413391, 54133921, 541339231, 5413392311, 54133923121, 541339231241, 5413392312463, 54133923124643, 541339231246433, 5413392312464369, 54133923124643743, 541339231246437473
Offset: 1

Views

Author

Robert G. Wilson v, Nov 28 2001

Keywords

Crossrefs

Cf. A065122.

Programs

  • Mathematica
    NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 5; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
    NestList[NextPrime[10#]&,5,20] (* Harvey P. Dale, Dec 25 2024 *)
  • PARI
    { for (n=1, 100, if (n>1, a=nextprime(10*a), a=5); write("b065534.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 21 2009

A065537 a(n) is smallest prime > 10*a(n-1), a(1) = 7.

Original entry on oeis.org

7, 71, 719, 7193, 71933, 719333, 7193357, 71933597, 719335993, 7193359933, 71933599363, 719335993631, 7193359936331, 71933599363319, 719335993633291, 7193359936332919, 71933599363329217, 719335993633292261
Offset: 1

Views

Author

Robert G. Wilson v, Nov 28 2001

Keywords

Crossrefs

Programs

  • Mathematica
    NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 7; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
  • PARI
    { for (n=1, 100, if (n>1, a=nextprime(10*a), a=7); write("b065537.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 21 2009

A100893 a(n) = smallest n-digit prime formed by appending a digit to a(n-1); a(1) = 2.

Original entry on oeis.org

2, 23, 233, 2333, 23333
Offset: 1

Views

Author

Jorge Coveiro, Jan 10 2005

Keywords

Comments

This sequence is finite because there is no prime a(6) since 233331,233333,233337,233339 are not prime.
This is an initial subsequence of A048549, A065122, A088603, and A127889; and for any b, the base b analog of this sequence is an initial subsequence of the base b analog of each of these three sequences. [From Franklin T. Adams-Watters, Jun 27 2009]

Examples

			a(1)=2
a(2)=23
a(3)=233
a(4)=2333
a(5)=23333
		

A065538 a(n) is smallest prime > 10*a(n-1), a(1) = 11.

Original entry on oeis.org

11, 113, 1151, 11519, 115201, 1152023, 11520269, 115202701, 1152027101, 11520271019, 115202710219, 1152027102209, 11520271022149, 115202710221517, 1152027102215173, 11520271022151733, 115202710221517367
Offset: 1

Views

Author

Robert G. Wilson v, Nov 28 2001

Keywords

Crossrefs

Cf. A065122.

Programs

  • Mathematica
    NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 11; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]

A065539 a(n) is smallest prime > 10*a(n-1), a(1) = 13.

Original entry on oeis.org

13, 131, 1319, 13217, 132173, 1321753, 13217531, 132175313, 1321753177, 13217531771, 132175317727, 1321753177271, 13217531772769, 132175317727727, 1321753177277287, 13217531772772933, 132175317727729369
Offset: 1

Views

Author

Robert G. Wilson v, Nov 28 2001

Keywords

Crossrefs

Cf. A065122.

Programs

  • Mathematica
    NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 13; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
Showing 1-7 of 7 results.