Search: id:A002523 Results 1-1 of 1 results found. %I A002523 %S A002523 1,2,17,82,257,626,1297,2402,4097,6562,10001,14642,20737, %T A002523 28562,38417,50626,65537,83522,104977,130322,160001,194482, %U A002523 234257,279842,331777,390626,456977,531442,614657,707282 %N A002523 n^4 + 1. %C A002523 Let Phi_k(x) be the k-th cyclotomic polynomial and form the sequence Phi_k(0), Phi_k(1), Phi_k(2), ... This gives A000027 (k=2), A002061 (k=3), A002522 (k=4), A053699 (k=5), A002061 (k=6), A053716 (k=7), A002523 (k=8), A060883 (k=9), A060884 (k=10), A060885 (k=11), A060886 (k=12), A060887 (k=13), A060888 (k=14), A060889 (k=15), A060890 (k=16), A060891 (k=18), A060892 (k=20), A060893 (k=24), A060894 (k=30), A060895 (k=32), A060896 (k=36). %C A002523 All odd prime factors of a(n) are congruent to 1 modulo 8. - Nick Hobson Jan 14 2007 %C A002523 Lee and Murty, p. 685: "In spite of these remarkable advances, we are still unable to determine if n^4 + 1 is infinitely often a squarefree number". - Jonathan Vos Post (jvospost3(AT)gmail.com), Sep 18 2007 %D A002523 Jung-Jo Lee and M. Ram Murty, "Dirichlet series and hyperelliptic curves", Forum Math. 19(2007), 677-705. %D A002523 Mabkhout, M. (1993). "Minoration de P(x4+1)". Rend. Sem. Fac. Sci. Univ. Cagliari 63 (2): 135-148. %H A002523 Index entries for sequences related to linear recurrences with constant coefficients %F A002523 O.g.f.: -(1-3*x+17*x^2+7*x^3+2*x^4)/(-1+x)^5 . a(n) = 5a(n-1)-10a(n-2)+10a(n-3)-5a(n-4)+a(n-5) - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 28 2008 %p A002523 with (combinat):seq(fibonacci(3,n^2), n=0..29); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 21 2008 %Y A002523 Cf. A005117. %Y A002523 Sequence in context: A155715 A054568 A060352 this_sequence A079889 A053786 A081744 %Y A002523 Adjacent sequences: A002520 A002521 A002522 this_sequence A002524 A002525 A002526 %K A002523 nonn %O A002523 0,2 %A A002523 N. J. A. Sloane (njas(AT)research.att.com). Search completed in 0.002 seconds