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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A134811 Giza primes.

Original entry on oeis.org

2, 3, 5, 7, 787, 34543, 345676543, 34567876543
Offset: 1

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Author

Omar E. Pol, Nov 30 2007

Keywords

Comments

Giza numbers (A134810) that are prime numbers. For n > 4 the structure of digits represents a pyramid at Giza. Also the top of a mountain. This sequence has only these 8 terms in base 10. For more information, see A134810.

Examples

			Illustration using the final term of this sequence:
  . . . . . . . . . . .
  . . . . . 8 . . . . .
  . . . . 7 . 7 . . . .
  . . . 6 . . . 6 . . .
  . . 5 . . . . . 5 . .
  . 4 . . . . . . . 4 .
  3 . . . . . . . . . 3
  . . . . . . . . . . .
  . . . . . . . . . . .
  . . . . . . . . . . .
		

References

  • Chris K. Caldwell and G. L. Honaker, Jr; Prime Curios!, The Dictionary of Prime Number Trivia, CreateSpace (2009), p. 209.

Crossrefs

Programs

  • Mathematica
    ups = Flatten[Table[Range[i, j - 1], {i, 1, 9}, {j, i + 1, 10}], 1];afull = Sort[  Map[ToExpression@StringJoin@Map[ToString, #[[;; -2]] ~Join~ Reverse[#]] &, ups]];Select[afull,PrimeQ] (* James C. McMahon, Apr 11 2025 *)

Formula

A000040 INTERSECT A134810. - Omar E. Pol, Mar 25 2011

Extensions

Reference and link added by Omar E. Pol, Mar 25 2011
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