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.

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