login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A334137 a(n) is the multiplicative inverse of A008514(n+1) modulo A008514(n). 2
0, 10, 19, 267, 338, 1868, 2069, 948, 7796, 5245, 22215, 17198, 3477, 43855, 21272, 95592, 60647, 186753, 135194, 45969, 263049, 139666, 467532, 301563, 55386, 559636, 241005, 948261, 543212, 1508854, 1001903, 318414, 1664590, 828391, 2587041, 1575400, 280143 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Daniel Hoyt, Table of n, a(n) for n = 0..10000

EXAMPLE

For a(0), compute the inverse of 1^4 + 2^4 mod 0^4 + 1^4 which is 0 mod 1, since everything mod 1 is 0.

For a(1), compute the inverse of 2^4 + 3^4 mod 1^4 + 2^4. The inverse of 97 mod 17 (or 12 mod 17) is 10 mod 17 since 10*12 = 120 has remainder 1 mod 17.

PROG

(PARI)

f(n) = n^4 + (n+1)^4;

a(n) = lift(1/Mod(f(n+1), f(n)));

(Python 3)

import gmpy2

soc = [] # sum of 4d-centered cubes

a=0

b=1

for i in range(100):

    c = a**4 + b**4

    soc.append(c)

    a += 1

    b += 1

A334137 = []

for i in range(len(soc)-1):

    c = gmpy2.invert(soc[i+1], soc[i])

    A334137.append(int(c))

print(', '.join([str(x) for x in A334137]))

CROSSREFS

Cf. A308215, A308217, A008514, A334121.

Sequence in context: A110368 A006050 A045646 * A212594 A255529 A023916

Adjacent sequences:  A334134 A334135 A334136 * A334138 A334139 A334140

KEYWORD

nonn,easy

AUTHOR

Daniel Hoyt, Apr 15 2020

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 12 12:31 EDT 2021. Contains 344947 sequences. (Running on oeis4.)