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.

A204938 Irregular table T(n,k) of primes such that all terms in row n have a prime companion that sums to 10^n.

Original entry on oeis.org

3, 5, 7, 3, 11, 17, 29, 41, 47, 53, 59, 71, 83, 89, 97, 3, 17, 23, 29, 47, 53, 59, 71, 89, 113, 137, 173, 179, 191, 227, 239, 257, 281, 317, 347, 353, 359, 383, 401, 431, 443, 479, 491, 509, 521, 557, 569, 599, 617, 641, 647, 653, 683, 719, 743, 761, 773
Offset: 1

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Author

Livio Rosai, Jan 27 2012

Keywords

Comments

Row 1 has 3 terms. Row 2 has 12 terms. Row 3 has 56 terms. All rows after the first have an even number of terms.

Examples

			3+7=10, 41+59=100, 317+683=1000.
		

Crossrefs

Cf. A107318 (number of terms in row n).
Cf. A126691, A126692, A126693 (primes that sum to 100, 1000, and 10000).

Programs

  • Mathematica
    Flatten[Table[ps = Prime[Range[PrimePi[10^n]]]; Select[ps, MemberQ[ps, 10^n - #] &], {n, 3}]] (* T. D. Noe, Jan 27 2012 *)