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.

Showing 1-2 of 2 results.

A213814 Primes that are sums of three, five and seven consecutive primes.

Original entry on oeis.org

311, 61643, 67141, 87853, 115361, 142799, 210031, 332489, 362309, 723823, 1149749, 1352863, 1444957, 1638733, 2197759, 2204117, 2299313, 2457473, 2765387, 3069263, 3212593, 3588647, 3633983
Offset: 1

Views

Author

Zak Seidov, Mar 04 2013

Keywords

Examples

			311 = 101 + 103 + 107 = 53 + 59 + 61 + 67 + 71 = 31 + 37 + 41 + 43 + 47 + 53 + 59.
		

Crossrefs

Subsequence of A211170.

Programs

  • Mathematica
    pr = Prime[Range[100000]]; to3 = Total /@ Partition[pr, 3, 1];
    to5 = Total /@ Partition[pr, 5, 1]; to7 = Total /@ Partition[pr, 7, 1];
    Select[Intersection[to3, to5, to7], PrimeQ]

A213914 Primes that are sums of three, five, seven and nine consecutive primes.

Original entry on oeis.org

28382041, 35213777, 64411157, 92223749, 132079147, 176955343, 253042357, 273128939, 365502299, 589730549, 644178091, 712541329, 827389151, 993274127, 1128722657, 1357950109, 1504974139, 1580552933, 1625263531, 1665516431, 1666495867, 1848493579, 2218519117
Offset: 1

Views

Author

Zak Seidov, Mar 05 2013

Keywords

Comments

The first case of sum of 11 consecutive primes is a(15) = 1128722657 = prime(5903277) +...+ prime(5903287) = 102611081 + 102611083 + 102611087 + 102611129 + 102611137 + 102611141 + 102611149 + 102611189 + 102611203 + 102611227 + 102611231. More such terms? - Zak Seidov, Dec 11 2017

Crossrefs

Subsequence of A213814. Cf. A211170.

Programs

  • Mathematica
    Block[{r = Prime@ Range[10^7], s}, Intersection @@ Array[Select[Total /@ Partition[r, 2 # + 1, 1], PrimeQ] &, 4] ] (* Michael De Vlieger, Dec 11 2017 *)

Extensions

a(10)-a(23) from Giovanni Resta, Mar 05 2013
Showing 1-2 of 2 results.