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A072537 a(1) = 2, a(2) = 3 and a(n) = the smallest prime which is a linear combination of all previous terms with all coefficients >= 1. 3
2, 3, 5, 13, 23, 53, 101, 211, 419, 839, 1669, 3343, 6689, 13381, 26759, 53527, 107053, 214129, 428221, 856459, 1712899, 3425803, 6851617, 13703231, 27406471, 54812957, 109625881, 219251761, 438503537, 877007063, 1754014121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..3318

FORMULA

For n >= 3, a(n) = A151800(S+(-1)^S) where S = Sum_{i=1..n-1} a(i). - Robert Israel, May 01 2019

MAPLE

A[1]:= 2: A[2]:= 3: S:= 5:

for i from 3 to 50 do

  if S::even then A[i]:= nextprime(S+1)

else A[i]:= nextprime(S-1)

  fi;

S:= S + A[i]

od:

seq(A[i], i=1..50); # Robert Israel, May 01 2019

CROSSREFS

Cf. A072536, A000040, A062391, A151800.

Sequence in context: A087898 A282236 A215306 * A289758 A089477 A099962

Adjacent sequences:  A072534 A072535 A072536 * A072538 A072539 A072540

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Aug 03 2002

EXTENSIONS

Corrected and extended by Sascha Kurz, Feb 12 2003

STATUS

approved

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Last modified September 22 00:33 EDT 2020. Contains 337275 sequences. (Running on oeis4.)