A335839 Integers whose sum of digits in base b is the same for every prime b up to 13.
0, 1, 2007986541, 2834822783, 31939595966, 33952616126, 42737313983, 44878987167, 309231463167, 318362221465, 415332522143, 881935644447, 1898245489647, 2077690289610, 2077690289611, 2153926044391, 3998461033469, 4285034622330, 4285034622331, 4294899857375
Offset: 1
Examples
31939595966 is 11101101111101111111000111010111110_2, 10001102220222120211202_3, 1010403014032331_5, 2210331041405_7, 12600084203_11 and 3020180615_13. In these bases, the sum of digits is 26, so 31939595966 is a term.
Links
- Thomas König, Table of n, a(n) for n = 1..19840
Programs
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Python
def digsum(n,b): s = 0 while n > 0: n, d = n//b, n%b s = s+d return s p = [2,3,5,7,11,13] n, a = 0, 0 while n <= 20: s2, i = digsum(a,2), 1 while i < len(p) and digsum(a,p[i]) == s2: i = i+1 if i == len(p): print(a, end = ", ") n = n+1 a = a+1 # A.H.M. Smeets, May 16 2021
Comments