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 A158024 Primes p such that all the digits needed to write the consecutive Primes from 2 to p fill exactly a square (no holes, no overlaps). 2
 2, 7, 29, 71, 101, 127, 191, 229, 317, 379, 499, 577, 733, 823, 10867, 11159, 12301, 12577, 13781, 14107, 15391, 15733, 17183, 17509, 19079, 19457, 21023, 21467, 23059, 23549, 25339, 25793, 27733, 28151, 30161, 30697, 32719, 33247, 35401 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The sides of the successive squares are given by A158025. Terms computed by Jean-Marc Falcoz. LINKS Robert Israel, Table of n, a(n) for n = 1..3000 Eric Angelini, Digit Spiral E. Angelini, Digit Spiral [Cached copy, with permission] EXAMPLE ...2...23...2357 .......57...1113 ............1719 ............2329 The primes fitting exactly in the SE corner of the above squares are 2, 7, 29. There is no 3X3 square where this is possible. MAPLE X:= 0: p:= 1: Res:= NULL: count:= 0: while count < 100 do   p:= nextprime(p);   X:= X + ilog10(p) + 1;   if issqr(X) then Res:= Res, p; count:= count+1 fi od: Res; # Robert Israel, Jan 13 2020 CROSSREFS Sequence in context: A285790 A083016 A062064 * A166940 A166939 A261182 Adjacent sequences:  A158021 A158022 A158023 * A158025 A158026 A158027 KEYWORD base,nonn AUTHOR Eric Angelini, Mar 11 2009 STATUS approved

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Last modified September 22 03:54 EDT 2020. Contains 337289 sequences. (Running on oeis4.)