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 21-22 of 22 results.

A294147 Initial member of 9 consecutive primes {a, b, c, d, e, f, g, h, i} such that (a + b + c)/3, (d + e + f)/3 and (g + h + i)/3 are all prime.

Original entry on oeis.org

63487, 462067, 830777, 847507, 1012159, 1049773, 1250611, 1268747, 1372537, 1372559, 1589657, 1988237, 2567557, 2696569, 2874673, 2967317, 3676111, 3718657, 4196987, 4255067, 4550867, 4669333, 5217911, 5225147, 5716031, 6019553, 6103171, 6725657, 6725731, 7143557
Offset: 1

Views

Author

K. D. Bajpai, Oct 23 2017

Keywords

Examples

			63487 is a term because it is the initial term of 9 consecutive primes {63487, 63493, 63499, 63521, 63527, 63533, 63541, 63559, 63577} = {a, b, c, d, e, f, g, h, i}: the arithmetic mean of three sets, i.e., (a + b + c)/ 3, (d + e + f)/3 and (g + h + i)/3 is prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime@ Range[5*10^5], 9, 1], Function[{a, b, c, d, e, f, g, h, i}, AllTrue[{(a + b + c)/3, (d + e + f)/3, (g + h + i)/3}, PrimeQ]] @@ # &][[All, 1]] (* Michael De Vlieger, Oct 23 2017 *)

A366414 Primes p such that p and the four previous primes are in arithmetic progression.

Original entry on oeis.org

9843139, 37772549, 53868769, 71427877, 78364669, 79080697, 98150141, 99591553, 104437009, 106457629, 111267539, 121174931, 121174961, 168236239, 199450219, 203909011, 207068923, 216618307, 230952979, 234058991, 235524901, 253412437, 263651281, 268843153, 294485483, 296239907
Offset: 1

Views

Author

Harvey P. Dale, Oct 09 2023

Keywords

Examples

			9843019, 9843049, 9843079, 9843109, 9843139 are the 5 consecutive primes starting from A059044(1) and ending at a(1).
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[10^7]],5,1],Length[Union[Differences[#]]]==1&][[;;,5]]
Previous Showing 21-22 of 22 results.