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 A051478 a(n) is the number of values k satisfying phi(k) = 4*n+2, n>0. 1
 4, 2, 0, 4, 2, 0, 2, 0, 0, 4, 2, 0, 2, 2, 0, 2, 2, 0, 2, 2, 0, 0, 0, 0, 2, 2, 2, 0, 0, 0, 2, 2, 0, 2, 0, 0, 2, 0, 0, 4, 2, 0, 0, 2, 0, 0, 2, 0, 2, 0, 0, 2, 0, 0, 2, 2, 0, 0, 2, 0, 0, 2, 0, 0, 2, 0, 2, 0, 0, 2, 0, 0, 2, 0, 0, 2, 2, 0, 0, 0, 0, 2, 0, 0, 2, 2, 0, 0, 2, 0, 2, 0, 0, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Sequence consists of only 0's, 2's and 4's. LINKS Table of n, a(n) for n=1..103. EXAMPLE phi(k)=4*1+2 has 4 solutions (k=7, 9, 14, 18), so a(1)=4. CROSSREFS Cf. A000010, A032446, A051479. Sequence in context: A048819 A076114 A294666 * A121829 A021708 A016690 Adjacent sequences: A051475 A051476 A051477 * A051479 A051480 A051481 KEYWORD nonn AUTHOR Jud McCranie STATUS approved

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Last modified February 25 02:17 EST 2024. Contains 370308 sequences. (Running on oeis4.)