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A109986
Primes ordered alphabetically by where they occur in A000052.
4
5, 7, 3, 2, 89, 83, 11, 59, 53, 41, 47, 43, 19, 97, 17, 79, 71, 73, 61, 67, 13, 31, 37, 29, 23, 881, 887, 883, 811, 859, 857, 853, 809, 877, 863, 839, 829, 821, 827, 823, 587, 557, 541, 547, 509, 599, 593, 571, 577, 569, 563, 503, 521, 523, 487, 457, 449, 443
OFFSET
1,1
COMMENTS
A109987 is semiprimes ordered alphabetically by where they occur in A000052. A109988 is 3-almost primes ordered alphabetically by where they occur in A000052.
LINKS
EXAMPLE
a(1) = 5 because five is the first prime in alphabetical order.
a(5) = 89 because eighty-nine is the first 2-digit prime in alphabetical order.
MAPLE
V:= [seq(select(isprime, [$10^i..10^(i+1)-1]), i=0..3)]:
seq(op(V[i][sort(map(convert, V[i], english, 'And'),
output=permutation)]), i=1..nops(V)); # Robert Israel, Jun 17 2016
MATHEMATICA
alph = Last /@ Import["https://oeis.org/A000052/b000052.txt", "Table"]; Take[
Select[alph, PrimeQ], 58] (* Giovanni Resta, Jun 17 2016 *)
CROSSREFS
KEYWORD
base,easy,nonn,word
AUTHOR
Jonathan Vos Post, Jul 07 2005
EXTENSIONS
Corrected and extended by Giovanni Resta, Jun 17 2016
STATUS
approved