OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
a(n) ~ (n^2 log^2 n)/8. - Charles R Greathouse IV, Jun 03 2013
PROG
(PARI) lista(nn) = {for (n=1, nn, if (isprime(n) || isprime(n+1), print1(n*(n+1)/2, ", ")); ); } \\ Michel Marcus, Jun 03 2013
(PARI) print1(1); forprime(p=3, 7, print1(", "p*(p-1)/2", "p*(p+1)/2)) \\ Charles R Greathouse IV, Jun 03 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Giovanni Teofilatto, Nov 15 2008
EXTENSIONS
Missing terms 28=7*8/2, 91=13*14/2 etc. inserted by R. J. Mathar, Jan 30 2010
STATUS
approved