A076430 - OEIS

%I #3 Mar 02 2015 16:08:49

%S 1,70,1610,22715,170170,675376,2224824,5696295,21057190,52798270,

%T 111385170,261955560,414410780,628310711,1187225546,2369546790,

%U 3631067090,5339542890,8459444455,10969197540,15154637940,22349763995

%N Sum of squares of numbers that cannot be written as t*p_n + u*p_{n+1} for nonnegative integers t,u, where p_n is the n-th prime.

%D Fred. Schuh, Vragen betreffende een onbepaalde vergelijking, Nieuw Tijdschrift voor Wiskunde, 52 (1964-1965) 193-198.

%F p_n*p_{n+1}*(p_n-1)*(p_{n+1}-1)*(p_n*p_{n+1}-p_n-p_{n+1})/12

%p seq(ithprime(n)*ithprime(n+1)*(ithprime(n)-1)*(ithprime(n+1)-1)*(ithprime(n)*ithprime(n+1)-ithprime(n)-ithprime(n+1))/12,n=1..30);

%Y Cf. A076389, A076429.

%K nonn

%O 1,2

%A _Floor van Lamoen_, Oct 10 2002