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.

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A198171 Primes from merging of 7 successive digits in decimal expansion of Pi forbidding leading zeros.

Original entry on oeis.org

1592653, 6535897, 2643383, 5028841, 6939937, 3993751, 1170679, 8086513, 5822317, 1725359, 4930381, 2881097, 4612847, 3165271, 2712019, 1201909, 4914127, 1133053, 3841469, 1469519, 6951941, 9433057, 9326117, 4462379, 2749567, 5272489, 8912279, 8183011
Offset: 1

Views

Author

Harvey P. Dale, Oct 21 2011

Keywords

Comments

Leading zeros are not permitted, so each term is 7 digits in length.

Crossrefs

Programs

  • Mathematica
    With[{len=7},Select[FromDigits/@Partition[RealDigits[Pi,10,1000][[1]], len,1], IntegerLength[#]==len&&PrimeQ[#]&]]

A198172 Primes from merging of 8 successive digits in decimal expansion of Pi forbidding leading zeros.

Original entry on oeis.org

28841971, 41971693, 82534211, 42117067, 30664709, 31725359, 49303819, 75648233, 37867831, 71201909, 48566923, 26648213, 13393607, 25409171, 57595919, 21861173, 81932611, 79962749, 24891227, 30119491, 40656643, 30860213, 39494639, 39522473, 98609437, 53921717
Offset: 1

Views

Author

Harvey P. Dale, Oct 21 2011

Keywords

Comments

Leading zeros are not permitted, so each term is 8 digits in length.

Crossrefs

Programs

  • Mathematica
    With[{len=8},Select[FromDigits/@Partition[RealDigits[Pi,10,1000][[1]], len,1],IntegerLength[#]==len&&PrimeQ[#]&]]

A198173 Primes from merging of 9 successive digits in decimal expansion of Pi forbidding leading zeros.

Original entry on oeis.org

795028841, 502884197, 884197169, 971693993, 348253421, 421170679, 306647093, 812848111, 659334461, 233786783, 648566923, 346034861, 326648213, 829254091, 678925903, 959195309, 530921861, 938183011, 298336733, 798609437, 717629317, 320005681, 757789609
Offset: 1

Views

Author

Harvey P. Dale, Oct 21 2011

Keywords

Comments

Leading zeros are not permitted, so each term is 9 digits in length.

Crossrefs

Programs

  • Mathematica
    With[{len=9},Select[FromDigits/@Partition[RealDigits[Pi,10,1000][[1]], len,1],IntegerLength[#]==len&&PrimeQ[#]&]]

A198175 Primes from merging of 2 successive digits in decimal expansion of Pi.

Original entry on oeis.org

31, 41, 59, 53, 89, 97, 79, 23, 43, 83, 79, 41, 19, 97, 71, 37, 97, 59, 23, 89, 53, 11, 17, 67, 79, 13, 23, 47, 23, 31, 17, 53, 59, 11, 11, 17, 41, 19, 11, 59, 29, 89, 19, 97, 59, 61, 47, 23, 37, 67, 83, 31, 71, 19, 23, 61, 43, 13, 41, 73, 37, 31, 17, 29, 17
Offset: 1

Views

Author

Harvey P. Dale, Oct 21 2011

Keywords

Comments

Leading zeros are not permitted, so each term is 2 digits in length.

Crossrefs

Programs

  • Mathematica
    With[{len=2},Select[FromDigits/@Partition[RealDigits[Pi,10,1000][[1]], len,1],IntegerLength[#]==len&&PrimeQ[#]&]]

A198174 Primes from merging of 10 successive digits in decimal expansion of Pi, in the order of appearance.

Original entry on oeis.org

5926535897, 4197169399, 1693993751, 7510582097, 4825342117, 5822317253, 2841027019, 8521105559, 8954930381, 4756482337, 2712019091, 5432664821, 3266482133, 6072602491, 5588174881, 8815209209, 6282925409, 2540917153, 5903600113, 8204665213, 3841469519
Offset: 1

Views

Author

Harvey P. Dale, Oct 21 2011

Keywords

Comments

Leading zeros are not permitted, so each term is 10 digits in length.
See A104830 for the variant without this restriction. - M. F. Hasler, Nov 01 2014

Crossrefs

Cf., for Pi: A198175, A198170, A104824, A104825, A104826, A198171, A198172, A198173, A198174 (this) and A104830 (a variant).
Cf., for the Golden Ratio: A198177, A103773, A103789, A103793, A103808, A103809, A103810, A103811, A103812.
Cf., for the Euler-Mascheroni constant gamma: A198776, A198777, A198778, A198779, A198780, A198781, A198782, A198783, A198784.

Programs

  • Mathematica
    With[{len=10},Select[FromDigits/@Partition[RealDigits[Pi,10,1000][[1]], len,1],IntegerLength[#]==len&&PrimeQ[#]&]]
  • PARI
    A198174(n, x=Pi, m=10, silent=0)={m=10^m; for(k=1, default(realprecision), (isprime(p=x\.1^k%m)&&p*10>m)||next; silent||print1(p", "); n--||return(p))} \\ The optional arguments can be used to produce other sequences of this series (cf. Crossrefs). Use e.g. \p999 to set precision to 999 digits. - M. F. Hasler, Nov 01 2014

A198776 Primes from merging of 2 successive digits in decimal expansion of Euler-Mascheroni constant.

Original entry on oeis.org

53, 2, 43, 31, 59, 59, 23, 59, 5, 67, 23, 67, 67, 67, 47, 29, 17, 67, 31, 47, 7, 5, 83, 41, 17, 73, 97, 23, 53, 53, 3, 37, 29, 37, 73, 37, 73, 37, 67, 73, 79, 59, 47, 73, 3, 67, 53, 23, 31, 17, 61, 11, 11, 19, 7, 79, 47, 79, 37, 5, 2, 29, 13, 47, 61, 2, 29
Offset: 1

Views

Author

Harvey P. Dale, Oct 29 2011

Keywords

Comments

Leading zeros are permitted, so some terms may be less than 2 digits in length.

Crossrefs

Programs

  • Mathematica
      egp[len_]:=Module[{egterms=FromDigits/@Partition[RealDigits[EulerGamma, 10, 1000][[1]],len,1]},Select[egterms,PrimeQ[#]&]];egp[2]
    Select[FromDigits/@Partition[RealDigits[EulerGamma,10,500][[1]],2,1],PrimeQ] (* Harvey P. Dale, Mar 19 2020 *)

A198784 Primes from merging of 10 successive digits in decimal expansion of Euler-Mascheroni constant (in the order of appearance).

Original entry on oeis.org

7215664901, 1566490153, 3286060651, 6060651209, 9008240243, 4310421593, 2159335939, 9235988057, 8486772677, 8070824809, 2836224173, 3622417399, 3997644923, 33374293, 2582470949, 6008735203, 87352039, 3151776611, 5015079847, 7400299213, 3139925401, 3754139549
Offset: 1

Views

Author

Harvey P. Dale, Oct 29 2011

Keywords

Comments

Leading zeros are permitted, so some terms are less than 10 digits in length.
See A104944 for the variant where no leading zeros are allowed. - M. F. Hasler, Nov 01 2014

Crossrefs

For the Euler-Mascheroni constant, see also A198776, A198777, A198778, A198779, A198780, A198781, A198782, A198783, A198784 (this sequence) and A104944 (a variant).
For the Golden Ratio, see A198177, A103773, A103789, A103793, A103808, A103809, A103810, A103811, A103812.

Programs

  • Mathematica
    egp[len_]:=Module[{egterms=FromDigits/@Partition[RealDigits[EulerGamma, 10, 1000][[1]],len,1]},Select[egterms,PrimeQ[#]&]]; egp[10]
  • PARI
    list_A198784(x=Euler,m=10)=m=10^m;for(k=1,default(realprecision),isprime(p=x\.1^k%m)&&print1(p",")) \\ The optional arguments can be used to produce other sequences of this series (cf. Crossrefs). Use e.g. \p999 to set precision to 999 digits. - M. F. Hasler, Nov 01 2014

A198777 Primes from merging of 3 successive digits in decimal expansion of Euler-Mascheroni constant.

Original entry on oeis.org

577, 431, 421, 593, 359, 593, 359, 677, 677, 467, 709, 947, 467, 463, 631, 809, 401, 283, 241, 173, 739, 997, 449, 353, 3, 337, 293, 937, 373, 733, 337, 773, 673, 739, 709, 491, 853, 233, 331, 151, 661, 211, 199, 79, 479, 937, 857, 2, 29, 547, 29, 43, 421
Offset: 1

Views

Author

Harvey P. Dale, Oct 29 2011

Keywords

Comments

Leading zeros are permitted, so some terms are less than 3 digits in length.

Crossrefs

Programs

  • Mathematica
    egp[len_]:=Module[{egterms=FromDigits/@Partition[RealDigits[EulerGamma, 10, 1000][[1]],len,1]},Select[egterms,PrimeQ[#]&]]; egp[3]

A198778 Primes from merging of 4 successive digits in decimal expansion of Euler-Mascheroni constant A001620.

Original entry on oeis.org

577, 421, 3359, 3593, 5939, 9923, 8677, 2677, 6709, 6947, 6329, 2917, 4951, 1447, 401, 4283, 2417, 6449, 5003, 3733, 3767, 7673, 9491, 2039, 853, 5323, 6211, 4793, 7937, 857, 7057, 29, 3547, 6043, 587, 6733, 7331, 3313, 1399, 7541, 5413, 4139, 8423, 4877, 503, 8431, 3109, 1093, 9973, 3613, 8893, 8933, 17, 7247
Offset: 1

Views

Author

Harvey P. Dale, Oct 29 2011

Keywords

Comments

In contrast to A104938, leading zeros are allowed here, which explains the terms having fewer than 4 digits; e.g., a(32)=29 comes from consecutive digits "...0029..." starting at the 268th decimal digit of gamma (if the initial "0." counts as the first digit). - M. F. Hasler, Oct 31 2011

Examples

			The first four decimal digits of gamma = 0.5772... form the prime 577=a(1).
		

Crossrefs

Programs

  • Maple
    Digits := 420 ;
    for sh from 3 do
            p := floor(gamma*10^sh) mod 10000 ;
            if isprime(p) then
                    printf("%d,",p);
            end if;
    end do: # R. J. Mathar, Oct 31 2011
  • Mathematica
    (* see A104938 for Mmca code *)
    Join[{577},Select[FromDigits/@Partition[RealDigits[EulerGamma,10,1000][[1]],4,1],PrimeQ]] (* Harvey P. Dale, May 07 2019 *)
  • PARI
    L=10^4;for(i=3,999,isprime(p=Euler\.1^i%L)&print1(p",")) \\ M. F. Hasler, Oct 31 2011

A198779 Primes from merging of 5 successive digits in decimal expansion of Euler-Mascheroni constant.

Original entry on oeis.org

64901, 59399, 48677, 77267, 26777, 66467, 36947, 6329, 32917, 17467, 49807, 24809, 92353, 50033, 74293, 42937, 37337, 33773, 79259, 24709, 70949, 9491, 16567, 70853, 53233, 33151, 31517, 28621, 62119, 79847, 98479, 84793, 50857, 29921, 14669, 96043, 35267, 52673, 40129, 12967
Offset: 1

Views

Author

Harvey P. Dale, Oct 29 2011

Keywords

Comments

In contrast to A104939, leading zeros are permitted, so this sequence contains all elements of A104939 and additional primes having fewer than 5 digits.

Crossrefs

Programs

  • Mathematica
    egp[len_] := Module[{egterms = FromDigits /@ Partition[RealDigits[EulerGamma, 10, 400][[1]], len, 1]}, Select[egterms, PrimeQ[#] &]]; egp[5] (* Vincenzo Librandi, Apr 20 2013 *)
Previous Showing 21-30 of 38 results. Next