OFFSET
1,4
EXAMPLE
Between the 8th and 9th pairs of twin primes are 4 primes: (71,73) 79 83 89 97 (101,103), therefore a(8) = 79+83+89+97 = 348.
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Dec 20 2002
STATUS
approved