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A153005 Primes in toothpick sequence A153003. 0
7, 31, 127, 211, 487, 571, 643, 811, 1033, 1249, 1663, 1999, 2131, 2179, 2281, 2347, 2467, 3391, 4801, 5059, 6361, 7759, 8191, 8209, 8713, 8779, 8929, 9187, 9343, 9679, 9931, 10687, 13903, 14947, 19009, 19267, 19423, 25057, 26731, 28879, 33289, 35521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

MAPLE

read("transforms3") ; a139250 := BFILETOLIST("b139250.txt") ; A139250 := proc(n) global a139250; op(n+1, a139250) ; end: A153003 := proc(n) if n =0 then 0; else 1+3/4*(A139250(n+1)-3) ; fi; end: for n from 0 to 400 do p := A153003(n) ; if isprime(p) then printf("%d, ", p) ; fi; od: # R. J. Mathar, Jul 13 2009

CROSSREFS

Cf. A139250, A139253, A152998, A152999, A153000, A153002, A153003, A153006, A153009.

Sequence in context: A002184 A002588 A036280 * A056909 A002147 A169785

Adjacent sequences:  A153002 A153003 A153004 * A153006 A153007 A153008

KEYWORD

nonn

AUTHOR

Omar E. Pol, Jan 02 2009

EXTENSIONS

More terms from R. J. Mathar, Jul 13 2009

STATUS

approved

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Last modified January 20 04:43 EST 2019. Contains 319323 sequences. (Running on oeis4.)