A076430 - OEIS

A076430

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.

1, 70, 1610, 22715, 170170, 675376, 2224824, 5696295, 21057190, 52798270, 111385170, 261955560, 414410780, 628310711, 1187225546, 2369546790, 3631067090, 5339542890, 8459444455, 10969197540, 15154637940, 22349763995

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

REFERENCES

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

LINKS

Table of n, a(n) for n=1..22.

FORMULA

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

MAPLE

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);

CROSSREFS

Cf. A076389, A076429.

Sequence in context: A298973 A278548 A107421 * A006296 A047835 A133312

Adjacent sequences: A076427 A076428 A076429 * A076431 A076432 A076433

KEYWORD

nonn

AUTHOR

Floor van Lamoen, Oct 10 2002

STATUS

approved