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A088849 Number of prime factors, with multiplicity, of numbers that can be expressed as the sum of two distinct 4th powers in exactly two distinct ways. 2
4, 4, 4, 4, 3, 4, 4, 4, 6, 4, 5, 6, 4, 4, 7, 5, 7, 4, 3, 5, 6, 5, 6, 5, 6, 4, 5, 5, 6, 5, 4, 5, 4, 4, 6, 6, 6, 6, 6, 6, 5, 5, 6, 5, 6, 6, 7, 5, 7, 5, 6, 4, 5, 6, 6, 6, 5, 6, 5, 6, 4, 6, 4, 7, 6, 7, 5, 4, 5, 4, 5, 4, 6, 6, 5, 6, 6, 6, 5, 7, 4, 5, 6, 4, 6, 5, 6, 4, 5, 8, 9, 5, 5, 6, 6, 5, 3, 5, 8, 5, 7, 5, 7, 6, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..105.

D. J. Bernstein, List of 516 primitive solutions p^4 + q^4 = r^4 + s^4

Cino Hilliard, p,q,r,s and evaluation of the Bernstein data

Cino Hilliard, Evaluation of the Bernstein data only

FORMULA

Bigomega(n) for n = a^4+b^4 = c^4+d^4 for distinct a, b, c, d. n=635318657, 3262811042, .., 680914892583617, .., 962608047985759418078417

EXAMPLE

The 16th entry in the Bernstein Evaluation =

680914892583617 = 17*17*89*61657*429361 = 5 factors. 5 is the 16th entry in the sequence.

PROG

(PARI) \ begin a new session and (back slash)r x4data.txt (evaluated Bernstein data) \ to the gp session. This will allow using %1 as the initial value. bigomegax4py42(n) = { for (i = 1, n, x = eval( Str("%", i) ); y=bigomega(x); print(y", ") ) }

CROSSREFS

Cf. A003824.

Sequence in context: A147563 A136213 A088848 * A251539 A123932 A010709

Adjacent sequences:  A088846 A088847 A088848 * A088850 A088851 A088852

KEYWORD

fini,nonn

AUTHOR

Cino Hilliard, Nov 24 2003

STATUS

approved

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Last modified December 11 18:34 EST 2019. Contains 329925 sequences. (Running on oeis4.)