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A035113
Numbers != 2 (mod 4) listed in order of increasing totient function phi (A000010).
4
1, 3, 4, 5, 8, 12, 7, 9, 15, 16, 20, 24, 11, 13, 21, 28, 36, 17, 32, 40, 48, 60, 19, 27, 25, 33, 44, 23, 35, 39, 45, 52, 56, 72, 84, 29, 31, 51, 64, 68, 80, 96, 120, 37, 57, 63, 76, 108, 41, 55, 75, 88, 100, 132, 43, 49, 69, 92, 47, 65, 104, 105, 112, 140, 144
OFFSET
1,2
LINKS
L. C. Washington, The Main Conjecture and Annihilation of Class Groups, In: Introduction to Cyclotomic Fields, Graduate Texts in Mathematics, vol 83 (1997) Springer, New York, NY.
EXAMPLE
phi(1)=1, phi(3)=2, phi(4)=2, phi(5)=4, ...
PROG
(Python) from sympy import totient as A000010
def lov(n): return sorted([[A000010(n), n] for n in range(1, n) if n%4 != 2])
print([x[1] for x in lov(200)][:100]) # Dumitru Damian, Feb 01 2022
KEYWORD
nonn,easy
EXTENSIONS
More terms from James A. Sellers
a(43) onward corrected by Sean A. Irvine, Sep 26 2020
STATUS
approved