A054570 Prime number spiral (clockwise, West spoke).

2, 19, 83, 199, 389, 641, 967, 1361, 1823, 2377, 3001, 3709, 4517, 5419, 6353, 7477, 8623, 9791, 11159, 12577, 14083, 15667, 17417, 19273, 21149, 23063, 25229, 27431, 29683, 32183, 34543, 37171, 39877, 42641, 45599, 48673, 51719, 54973, 58171

Offset

0,1

Links

Ivan Panchenko, Table of n, a(n) for n = 0..1000

Formula

8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is West, clockwise.

a(n) = A000040(A033951(n)). - R. J. Mathar, Aug 29 2018

Example

Begin a prime number spiral at shell 0 (prime 2), proceed clockwise, West.
From Omar E. Pol, Feb 19 2022: (Start)
The spiral with four terms in every spoke looks like this:
.
  227  101--103--107--109--113--127
   |     |                       |
  223   97   29---31---37---41  131
   |     |    |              |   |
  211   89   23    3----5   43  137
   |     |    |    |    |    |   |
  199   83   19    2    7   47  139
   |     |    |         |    |   |
  197   79   17---13---11   53  149
   |     |                   |   |
  193   73---71---67---61---59  151
   |                             |
  191--181--179--173--167--163--157
.
(End)

Mathematica

Table[ Prime[4n^2 + 3n + 1], {n, 0, 40} ]

Crossrefs

Cf. A033951, A054551, A054553, A054555, A054564, A054566, A054570, A053999.

Sequence in context: A240280 A327820 A331898 * A135436 A056005 A034572

Adjacent sequences: A054567 A054568 A054569 * A054571 A054572 A054573

Keyword

easy,nonn

Author

Enoch Haga and G. L. Honaker, Jr., Apr 10 2000

Extensions

Edited by Frank Ellermann, Feb 24 2002

Status

approved