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A164820
Numbers n such that n-th digit (after decimal point) of e and of Euler-Mascheroni constant gamma are the same.
2
4, 30, 33, 34, 48, 49, 52, 59, 60, 66, 96, 113, 115, 134, 146, 155, 163, 169, 175, 180, 193, 196, 200, 206, 211, 235, 251, 274, 288, 300, 302, 304, 330, 336, 338, 350, 354, 358, 368, 373, 381, 399, 412, 419, 430, 436, 438, 440, 491, 506, 536, 542, 552, 579
OFFSET
1,1
LINKS
EXAMPLE
e = 2.7182818284..., gamma = 0.5772156649...; fourth digit of e and fourth digit of gamma are both 2, hence 4 is in the sequence.
MAPLE
P:=proc(i) local a, b, c, d, n; a:=convert(evalf(gamma, 1000), string); b:=convert(evalf(exp(1)-2, 1000), string); for n from 2 by 1 to i do if substring(a, n)=substring(b, n) then print(n-1); fi; od; end: P(900);
MATHEMATICA
With[{nn=600}, Position[Thread[{Rest[RealDigits[E, 10, nn+1][[1]]], RealDigits[ EulerGamma, 10, nn][[1]]}], {x_, x_}]]//Flatten (* Harvey P. Dale, Oct 08 2017 *)
PROG
(Magma) m:=600; e:=Exp(One(RealField(m+1))); se:=IntegerToString(Round(10^m*(e-2))); g:=EulerGamma(RealField(m)); sg:=IntegerToString(Round(10^m*g)); [ a: a in [1..m] | se[a] eq sg[a] ]; // Klaus Brockhaus, Sep 03 2009
CROSSREFS
Sequence in context: A159862 A364853 A298648 * A022387 A108559 A167395
KEYWORD
easy,nonn,base
AUTHOR
EXTENSIONS
Edited and listed terms verified by Klaus Brockhaus, Sep 03 2009
STATUS
approved