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 A187088 Least odd k such that k*2^(2^n)+1 is prime. 1
 1, 1, 1, 1, 1, 43, 25, 21, 207, 223, 1125, 2577, 3091, 9165, 6223, 3493, 1063 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 LINKS Table of n, a(n) for n=0..16. Mark Rodenkirch: OpenPFGW (for running the PFGW the program). MATHEMATICA Table[k=1; While[! PrimeQ[k*2^2^n + 1], k=k+2]; k, {n, 0, 10}] PROG (PFGW) SCRIPT DIM nn, -1 DIM kk DIMS tt LABEL loopn SET nn, nn+1 SET kk, -1 LABEL loopk SET kk, kk+2 SETS tt, %d, %d\,; nn; kk PRP kk*2^(2^nn)+1, tt IF ISPRP THEN GOTO loopn GOTO loopk \PFGW -t FILE.txt FILE.txt = ABC \$a 43*2^(2^5)+1 25*2^(2^6)+1 21*2^(2^7)+1 207*2^(2^8)+1 223*2^(2^9)+1 1125*2^(2^10)+1 2577*2^(2^11)+1 3091*2^(2^12)+1 9165*2^(2^13)+1 6223*2^(2^14)+1 3493*2^(2^15)+1 1063*2^(2^16)+1 CROSSREFS Sequence in context: A097398 A225210 A033363 * A127147 A298078 A291494 Adjacent sequences: A187085 A187086 A187087 * A187089 A187090 A187091 KEYWORD nonn AUTHOR Pierre CAMI, Mar 08 2011 STATUS approved

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Last modified September 8 20:40 EDT 2024. Contains 375759 sequences. (Running on oeis4.)