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 1-5 of 5 results.

A106093 Primes with maximal digit = 9.

Original entry on oeis.org

19, 29, 59, 79, 89, 97, 109, 139, 149, 179, 191, 193, 197, 199, 229, 239, 269, 293, 349, 359, 379, 389, 397, 409, 419, 439, 449, 479, 491, 499, 509, 569, 593, 599, 619, 659, 691, 709, 719, 739, 769, 797, 809, 829, 839, 859, 907, 911, 919, 929, 937, 941, 947
Offset: 1

Views

Author

Zak Seidov and Robert G. Wilson v, May 07 2005

Keywords

Comments

Differs from A062679 in 95th term = 1693; A062679(95) = 1691 = 19*89.

Links

Crossrefs

Cf. A062679.
Cf. A106100, A106099, A106098, A106097, A106096, A106095, A106094.

Programs

  • Magma
    [p: p in PrimesUpTo(2000) | 9 in Intseq(p)]; // Vincenzo Librandi, Nov 22 2015
  • Mathematica
    Select[Prime[Range[200]], Max[IntegerDigits[ # ]]==9&]
  • PARI
    forprime(p=2, 1e3, if(vecmax(digits(p)) == 9, print1(p, ", "))) \\ Altug Alkan, Nov 22 2015

A106100 Primes with maximal digit = 2.

Original entry on oeis.org

2, 211, 1021, 1201, 2011, 2111, 2221, 10211, 12011, 12101, 12211, 20011, 20021, 20101, 20201, 21001, 21011, 21101, 21121, 21211, 21221, 22111, 101021, 101221, 102001, 102101, 102121, 110221, 111121, 111211, 112111, 112121, 120011, 120121
Offset: 1

Views

Author

Zak Seidov, May 07 2005

Keywords

Comments

Subsequence of A036953. Prime numbers p such that A209928(p) = 2. Complement of A221698 with respect to A221697. [Jaroslav Krizek, Jan 22 2013]

Links

Crossrefs

Cf. A106093, A106094, A106095, A106096, A106097, A106098, A106099.

Programs

  • Maple
    N:= 6: # to get all terms of up to N digits
M2:= {1};M1:= {1}:
for d from 1 to N-1 do
  M2:= map(t -> (t, t+10^d, t+2*10^d), M2);
  M1:= map(t -> (t, t+10^d), M1);
od:
sort(convert({2} union select(isprime,M2 minus M1),list)); # Robert Israel, Jun 19 2016
  • Mathematica
    Select[Prime[Range[10000]], Max[IntegerDigits[ # ]]==2&]
  • PARI
    isok(p) = isprime(p) && (vecmax(digits(p)) == 2); \\ Michel Marcus, Jan 02 2019

Extensions

More terms from Rick L. Shepherd, May 22 2005

A106099 Primes with maximal digit = 3.

Original entry on oeis.org

3, 13, 23, 31, 103, 113, 131, 223, 233, 311, 313, 331, 1013, 1031, 1033, 1103, 1123, 1213, 1223, 1231, 1301, 1303, 1321, 2003, 2113, 2131, 2203, 2213, 2311, 2333, 3001, 3011, 3023, 3121, 3203, 3221, 3301, 3313, 3323, 3331
Offset: 1

Views

Author

Zak Seidov, May 07 2005

Keywords

Links

Crossrefs

Cf. A106093, A106094, A106095, A106096, A106097, A106098, A106100.

Programs

  • Maple
    Res:= 3: count:= 1:
A:= {3}: B:= {$1..2}:
for d from 2 while count < 100 do
  A:= {seq(seq(10*a+i,i=0..3),a=A), seq(10*b+3,b=B)}:
  B:= {seq(seq(10*b+i,i=0..2),b=B)}:
  S:= sort(convert(select(isprime,A),list));
  count:= count + nops(S);
  Res:= Res, op(S);
od:
Res; # Robert Israel, Jan 01 2019
  • Mathematica
    Select[Prime[Range[600]], Max[IntegerDigits[ # ]]==3&]

A106098 Primes with maximal digit = 4.

Original entry on oeis.org

41, 43, 241, 401, 421, 431, 433, 443, 1423, 1433, 2141, 2143, 2243, 2341, 2411, 2423, 2441, 3041, 3343, 3413, 3433, 4001, 4003, 4013, 4021, 4111, 4133, 4201, 4211, 4231, 4241, 4243
Offset: 1

Views

Author

Zak Seidov, May 07 2005

Keywords

Links

Crossrefs

Cf. A106100, A106099, A106097, A106096, A106095, A106094, A106093.

Programs

  • Mathematica
    Select[Prime[Range[600]], Max[IntegerDigits[ # ]]==4&]

A283608 Numbers whose largest decimal digit is 5.

Original entry on oeis.org

5, 15, 25, 35, 45, 50, 51, 52, 53, 54, 55, 105, 115, 125, 135, 145, 150, 151, 152, 153, 154, 155, 205, 215, 225, 235, 245, 250, 251, 252, 253, 254, 255, 305, 315, 325, 335, 345, 350, 351, 352, 353, 354, 355, 405, 415, 425, 435, 445, 450, 451, 452, 453, 454
Offset: 1

Views

Author

Jaroslav Krizek, Mar 19 2017

Keywords

Comments

Numbers n such that A054055(n) = 5.
Number of terms less than 10^n is 6^n - 5^n.
Subsequence of A011535. - David A. Corneth, Mar 25 2017
Prime terms are in A106097.

Links

Crossrefs

Cf. A011535, A054055, A106097.
Cf. Sequences of numbers whose largest decimal digit is k (for k = 1..9): A007088 (k = 1), A277964 (k = 2), A277965 (k = 3), A277966 (k = 4), this sequence (k = 5), A283609 (k = 6), A283610 (k = 7), A283611 (k = 8), A011539 (k = 9).

Programs

  • GAP
    Filtered([1..500],n->Maximum(ListOfDigits(n))=5); # Muniru A Asiru, Feb 27 2019
  • Magma
    [n: n in [1..100000] | Maximum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 5];
  • Mathematica
    Select[Range[1000], Max[IntegerDigits[#]] == 5 &] (* Giovanni Resta, Mar 19 2017 *)
  • PARI
    for(n=1, 500, if(vecmax(digits(n))==5, print1(n,", "))) \\ Indranil Ghosh, Mar 19 2017
  • PARI
    nxt(n) = {my(d = digits(n), i, j=0, t=0); forstep(i=#d,1,-1, if(d[i]!=5, j=i; break)); if(j>0, d[j]++; if(d[j]==5, for(k=j+1,#d,d[k]=0)); if(j<#d && d[j+1]==5, for(k=j+1,#d-1,d[k]=0)); for(k=1,j-1, if(d[k]==5,for(i=j+1, #d, d[i] = 0);break)), d = vector(#d+1); d[1]=1; d[#d]=5);sum(i=1, #d, d[i]*10^(#d-i))} \\ David A. Corneth, Mar 25 2017
  • Python
    from sympy.ntheory.factor_ import digits
print([n for n in range(1, 501) if max(digits(n)[1:])==5]) # Indranil Ghosh, Mar 19 2017
Showing 1-5 of 5 results.

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