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A059661 Like A059459, but each term must be greater than the previous ones. 5
2, 3, 7, 23, 31, 4127, 4159, 20543, 134238271, 134238527, 167792959, 1241534783, 3389018431, 72108495167, 72108503359, 72108765503, 2722258935367507707706996859526254457151 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..17.

N. J. A. Sloane, Maple implementations of XORnos and DIFF

MAPLE

flip_primes_asc_search := proc(a, upto_bit, upto_length) local i, n, t; if(nops(a) >= upto_length) then RETURN(a); fi; t := a[nops(a)]; for i from 0 to upto_bit do n := XORnos(t, (2^i)); if(isprime(n) and (n > t)) then print([op(a), n]); RETURN(flip_primes_asc_search([op(a), n], upto_bit, upto_length)); fi; od; RETURN([op(a), `and no more`]); end;

E.g. call as: flip_primes_asc_search([2], 512, 21);

MATHEMATICA

uptobit = 512; uptolength = 17; Clear[f]; f[a_] := f[a] = Module[{n, i, t}, If[Length[a] >= uptolength, Return[a]]; t = a[[-1]]; For[i = 0, i <= uptobit, i++, n = BitXor[t, 2^i]; If[PrimeQ[n] && n > t, Return[f[Append[ a, n]]]]]]; A059661 = f[{2}] (* Jean-Fran├žois Alcover, Mar 07 2016, adapted from Maple *)

CROSSREFS

Sequence in context: A278477 A118883 A061712 * A214704 A231075 A072686

Adjacent sequences:  A059658 A059659 A059660 * A059662 A059663 A059664

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Feb 03 2001

STATUS

approved

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Last modified October 19 13:01 EDT 2019. Contains 328222 sequences. (Running on oeis4.)