OFFSET
1,2
REFERENCES
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 844.
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
PROG
(PARI) {isprimepower(n)=matsize(factor(n))[1]==1} for(n=1, 400, if(isprimepower(n)&&(isprimepower(n-2)||isprimepower(n+2)), print1(n", "))) \\ Ralf Stephan, Aug 20 2004
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jun 14 2001
STATUS
approved