A240580 Numbers n such that DigitSum(5^n) > DigitSum(5^(n+1)).

4, 10, 11, 12, 16, 18, 24, 27, 28, 32, 34, 36, 39, 44, 45, 49, 51, 52, 57, 58, 60, 61, 62, 63, 64, 69, 75, 76, 77, 78, 80, 83, 84, 87, 88, 90, 91, 94, 96, 97, 100, 103, 106, 107, 108, 113, 114, 115, 118, 119, 124, 129, 130, 132, 135, 138, 139, 142, 143, 144, 149

Offset

1,1

Links

K. D. Bajpai, Table of n, a(n) for n = 1..1000

Example

The digitsum(5^4) = 13 > 11 = digitsum(5^(4+1)). Hence, 4 appears in the sequence.
The digitsum(5^11) = 38 > 28 = digitsum(5^(11+1)). Hence, 11 appears in the sequence.

Maple

a := proc(n) local a, b, d, e; a:=5^n; b:=add( i, i = convert((a), base, 10))(a); d:=5^(n+1); e:=add( i, i = convert((d), base, 10))(d); if b > e then RETURN (n); fi; end: seq(a(n), n=1..300);

Mathematica

k=Table[Total[IntegerDigits[5^n, 10]], {n, 1, 300}]; Flatten[Position[Greater@@@Partition[k, 2, 1], True]]

Crossrefs

Cf. A186775 ( numbers n: digitsum(2^(n)) > digitsum(2^(n+1)) ),

A239935 ( numbers n: digitsum(3^n) > digitSum(3^(n+1)) ).

Sequence in context: A355497 A045855 A244216 * A102535 A074226 A106631

Adjacent sequences: A240577 A240578 A240579 * A240581 A240582 A240583

Keyword

nonn,base

Author

K. D. Bajpai, Apr 08 2014

Status

approved