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A193244 Numbers that are the sum of three biquadrates (fourth powers) in more than one way. 1
16562, 28593, 35378, 43218, 54977, 94178, 106353, 122018, 134162, 137633, 149058, 181202, 195122, 198497, 235298, 235553, 264113, 264992, 300833, 318402, 324818, 364658, 384833, 439922, 457488, 462722, 514098, 522242, 566048, 611618, 624962 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Erroneous version of A309762. - Ilya Gutkovskiy, Aug 15 2019
A subsequence of A003337. Lists the indices such that A193243(n) > 1.
LINKS
EXAMPLE
a(1) = 16562 = 1^4 + 9^4 + 10^4 = 5^4 + 6^4 + 11^4, and this is the least number having two such decompositions.
PROG
(PARI) is_A000404(n)={ for( i=1, #n=factor(n)~%4, n[1, i]==3 & n[2, i]%2 & return); n & ( vecmin(n[1, ])==1 || (n[1, 1]==2 & n[2, 1]%2))} \\ M. F. Hasler, Feb 07 2009
(PARI) for(n=1, 9e9, is_A000404(n) && A193243(n)>1 && print1(n", "))
CROSSREFS
Sequence in context: A253759 A091089 A109028 * A240901 A234894 A283028
KEYWORD
nonn
AUTHOR
M. F. Hasler, Jan 01 2013
STATUS
approved

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Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)