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A005073 Sum of 4th powers of primes = 1 mod 3 dividing n. 5
0, 0, 0, 0, 0, 0, 2401, 0, 0, 0, 0, 0, 28561, 2401, 0, 0, 0, 0, 130321, 0, 2401, 0, 0, 0, 0, 28561, 0, 2401, 0, 0, 923521, 0, 0, 0, 2401, 0, 1874161, 130321, 28561, 0, 0, 2401, 3418801, 0, 0, 0, 0, 0, 2401, 0, 0, 28561, 0, 0, 0, 2401, 130321, 0, 0, 0, 13845841, 923521, 2401, 0, 28561, 0, 20151121, 0, 0, 2401, 0, 0, 28398241, 1874161 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10001

FORMULA

Additive with a(p^e) = p^4 if p = 1 (mod 3), 0 otherwise.

PROG

(Scheme) (define (A005073 n) (if (= 1 n) 0 (+ (A000583 (if (= 1 (modulo (A020639 n) 3)) (A020639 n) 0)) (A005073 (A028234 n))))) ;; Antti Karttunen, Jul 09 2017

(PARI) a(n) = my(f=factor(n)); sum(k=1, #f~, if (((p=f[k, 1])%3) == 1, p^4)); \\ Michel Marcus, Jul 10 2017

CROSSREFS

Cf. A000583, A005070, A005071, A005072.

Sequence in context: A235414 A235259 A321638 * A176767 A018865 A186488

Adjacent sequences:  A005070 A005071 A005072 * A005074 A005075 A005076

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Antti Karttunen, Jul 09 2017

STATUS

approved

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Last modified May 24 14:36 EDT 2022. Contains 354037 sequences. (Running on oeis4.)