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.

Previous Showing 11-17 of 17 results.

A179914 Primes with six embedded primes.

Original entry on oeis.org

1733, 1973, 2113, 2137, 2237, 2311, 2347, 2371, 2713, 2719, 2837, 2953, 2971, 3373, 3673, 3719, 3733, 3739, 4337, 4373, 4397, 4673, 5231, 5233, 5347, 5479, 6131, 6197, 6317, 6733, 6737, 7193, 7331, 7523, 8237, 8317, 8537, 9719, 10313, 10337, 10937
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) = 6.

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Programs

  • Haskell
    import Data.List (elemIndices)
a179914 n = a179914_list !! (n-1)
a179914_list = map (a000040 . (+ 1)) $ elemIndices 6 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 1330, f@# == 7 &]

A179915 Primes with seven embedded primes.

Original entry on oeis.org

1373, 3137, 3797, 5237, 6173, 11173, 11311, 11353, 11719, 11731, 11971, 12113, 12239, 12347, 12377, 12953, 12973, 13127, 13177, 13217, 13537, 13597, 13679, 13709, 13711, 13723, 13729, 13751, 13757, 13759, 13799, 13967, 13997, 15137
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) = 7.

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Programs

  • Haskell
    import Data.List (elemIndices)
a179915 n = a179915_list !! (n-1)
a179915_list = map (a000040 . (+ 1)) $ elemIndices 7 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 1770, f@# == 8 &]

A179916 Primes with eight embedded primes.

Original entry on oeis.org

12373, 12379, 12713, 13171, 15233, 17333, 17359, 17971, 19373, 19379, 21139, 21319, 22973, 23167, 23197, 23311, 23473, 23537, 23593, 23671, 23677, 23761, 23773, 23977, 24113, 24137, 24179, 24197, 24317, 24337, 24379, 24733, 25237
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) = 8.

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Programs

  • Haskell
    import Data.List (elemIndices)
a179916 n = a179916_list !! (n-1)
a179916_list = map (a000040 . (+ 1)) $ elemIndices 8 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 2790, f@# == 9 &]

A179917 Primes with nine embedded primes.

Original entry on oeis.org

11317, 19739, 19973, 21317, 21379, 22397, 22937, 23117, 23173, 23371, 23971, 24373, 26317, 27197, 29173, 29537, 32719, 33739, 33797, 37397, 39719, 51137, 51973, 52313, 53173, 53479, 53719, 57173, 57193, 61379, 61979, 63179, 66173
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) = 9.

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Programs

  • Haskell
    import Data.List (elemIndices)
a179917 n = a179917_list !! (n-1)
a179917_list = map (a000040 . (+ 1)) $ elemIndices 9 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 6610, f@# == 10 &]

A179918 Primes with ten embedded primes.

Original entry on oeis.org

23719, 31379, 52379, 111373, 111731, 111733, 112397, 113117, 113167, 113723, 113759, 113761, 115237, 117191, 117431, 121139, 122971, 123113, 123373, 123479, 123731, 124337, 126173, 126317, 127139, 127733, 127739, 127973, 129733, 131171
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) = 10.

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Programs

  • Haskell
    import Data.List (elemIndices)
a179918 n = a179918_list !! (n-1)
a179918_list = map (a000040 . (+ 1)) $ elemIndices 10 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 12280, f@# == 11 &]

A079075 "Memory" of fibonacci(n): the number of (previous) Fibonacci numbers contained as substrings in fibonacci(n).

Original entry on oeis.org

0, 1, 0, 0, 0, 0, 3, 3, 1, 1, 1, 2, 2, 1, 2, 1, 3, 3, 3, 1, 2, 2, 3, 2, 2, 6, 3, 4, 4, 3, 6, 6, 4, 3, 2, 5, 5, 4, 4, 8, 5, 3, 2, 4, 5, 4, 6, 3, 2, 5, 5, 6, 5, 5, 7, 6, 5, 6, 4, 6, 6, 6, 7, 7, 4, 5, 8, 6, 3, 6, 7, 5, 6, 8, 6, 6, 5, 6, 8, 7, 6, 7, 6, 5, 5, 6, 7, 5, 4, 5, 6, 8, 7, 6, 5, 6, 8, 8, 10, 6
Offset: 1

Views

Author

Joseph L. Pe, Feb 02 2003

Keywords

Examples

			The (previous) Fibonacci numbers contained as substrings in fibonacci(7) = 13 are fibonacci(1) = 1, fibonacci(2) = 1, fibonacci(4) = 3. Hence a(7) = 3. 13 is the smallest Fibonacci number with memory = 3.

Crossrefs

Cf. A079066.

Programs

  • Mathematica
    ub = 100; tfib = Table[ToString[Fibonacci[i]], {i, 1, ub}]; a = {}; For[i = 1, i <= ub, i++, m = 0; For[j = 1, j < i, j++, If[Length[StringPosition[tfib[[i]], tfib[[j]]]] > 0, m = m + 1]]; a = Append[a, m]]; a

A179924 Primes with embedded primes.

Original entry on oeis.org

13, 17, 23, 29, 31, 37, 43, 47, 53, 59, 67, 71, 73, 79, 83, 97, 103, 107, 113, 127, 131, 137, 139, 151, 157, 163, 167, 173, 179, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337
Offset: 1

Views

Author

Robert G. Wilson v, Aug 01 2010

Keywords

Comments

A079066(a(n)) > 0. - Reinhard Zumkeller, Jul 19 2011
Is there a prime such that the previous prime is embedded in it? - Ivan N. Ianakiev, Nov 09 2023. Answer from Amiram Eldar: No. If prime(n) is embedded in prime(n+1) then prime(n+1) has at least one digit more than prime(n), so prime(n+1) > 2 * prime(n). But according to Bertrand's postulate, prime(n+1) < 2*prime(n).

Links

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274, A179922.

Programs

  • Haskell
    import Data.List (findIndices)
a179924 n = a179924_list !! (n-1)
a179924_list = map (a000040 . (+ 1)) $ findIndices (> 0) a079066_list
-- Reinhard Zumkeller, Jul 19 2011
  • Mathematica
    f[n_] := Block[{id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[Partition[id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 68, f@# > 1 &]
Previous Showing 11-17 of 17 results.

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