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A161913
Numbers k such that A001223(k) <> A000005(k).
5
4, 9, 10, 11, 12, 15, 16, 19, 20, 21, 23, 25, 26, 28, 29, 30, 31, 33, 34, 35, 36, 37, 39, 40, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78
OFFSET
1,1
MAPLE
p2:=2:for n from 1 to 78 do p1:=p2:p2:=ithprime(n+1):if(p2-p1<>tau(n))then print(n); fi:od: # Nathaniel Johnston, Apr 15 2011
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Jul 04 2009
STATUS
approved