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A333474
Numbers k such that 2^k + 1 is divisible by the sum of its decimal digits.
0
0, 1, 2, 3, 9, 98, 135, 200, 665, 1782, 4230, 4521, 6815, 17010, 19635, 30338, 31365, 35427, 49555, 96619, 102897, 157850, 193734, 273050, 393225, 449217, 477333, 483310, 493350, 534465, 661815, 918918, 947925, 1050858, 1114690, 1134945, 1204686, 1350990, 1428105
OFFSET
1,3
COMMENTS
Numbers k such that A000051(k) is in A005349.
EXAMPLE
9 is in the sequence, because 2^9 + 1 = 513 is divisible by 5 + 1 + 3.
PROG
(Python)
print([i for i in range(5000) if (2**i+1)%sum([int(i) for i in str(2**i+1)]) == 0])
(PARI) isok(k) = my(x=2^k+1); !(x % sumdigits(x)); \\ Michel Marcus, Mar 23 2020
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Daniel Starodubtsev, Mar 23 2020
EXTENSIONS
More terms from Giovanni Resta, Mar 23 2020
STATUS
approved